LENGTH-ADJUSTABLE LINK FOR A BRACELET

TECHNICAL FIELD

[0001]The present invention relates to a length-adjustable link for a bracelet, in particular for a watch bracelet with links to enable the bracelet to be adjusted for comfort. The invention also relates to a wristwatch having a bracelet with links incorporating one or more adjustable links for adjusting the length of the bracelet.

BACKGROUND ART

[0002]Numerous solutions have already been proposed in the prior art for expandable clasps enabling the bracelet to be adjusted so as to fit comfortably, in particular on a watch, so that the length of the bracelet can be adjusted according to circumstances, in particular the ambient temperature, for optimum comfort. As an alternative, adjustable links have also been proposed, so that their length can be modified to make the bracelet more comfortable to wear. These solutions have the advantage of enabling the length of the bracelet to be adjusted more precisely and more easily than adjusting the length of a bracelet with links by adding or removing a link.

[0003]By way of example, CH695656 discloses an adjustable link whose link length can be adjusted in the longitudinal direction of the bracelet according to at least two different lengths. This link comprises at least two link elements, one of which is capable of sliding relative to the other between at least two indexed positions in the longitudinal direction of the bracelet. This link also includes a locking system for locking the link elements in the indexed positions. The locking system comprises a pusher connected to a lock and mounted on one of the link elements. Actuation of the pusher releases the lock from indexing means provided in the other of the link elements to allow relative movement between the two link elements to modify the length of the link.

[0004]A bracelet integrating this adjustable link has the disadvantage of having to remove the bracelet to modify its length. In addition, some parts of the mechanism are visible on the outside of the link, affecting the aesthetics of the bracelet.

[0005]CH706086 discloses another example of a known adjustable link. This link comprises two half-links, one of which has a rod while the other has a longitudinal channel for receiving the rod. The channel is profiled to allow the rod to pass through and to cooperate with locking means with elastic return integrated into the rod in order to lock the link in a short or extended configuration. The passage of the link from a retracted configuration to an extended position is achieved by elastic deformation of the rod.

[0006]A bracelet incorporating the above-mentioned link also has the disadvantage of having to remove the bracelet to modify its length. Furthermore, the link, in its extended configuration, has interstices that are prone to fouling. These interstices are difficult to access, making cleaning time-consuming. In addition, an additional part is mounted trapped between the two half-links to conceal the guiding and indexing means, which makes the manufacture of the link more complex, with a significant impact on its production cost and reliability.

[0007]EP2759222 discloses an adjustable link of the drawer type comprising a first half-link housed inside a second half-link. The first half-link comprises resilient return locking means designed to be housed in first and second cavities of the second half-link in order to lock the link in a retracted and extended configuration respectively. The length of the link is adjusted by pulling one and/or the other of the two half-links along an opposite direction in the longitudinal direction of the bracelet. It is therefore preferable to remove the bracelet for easy adjustment of its length.

[0008]EP2484245 discloses a link provided with two half-links and comprising, in particular, elastic return means enabling the position of one of the half-links to be adjusted relative to the other while ensuring that the position chosen by the user is maintained. This link therefore has no actuator for adjusting its length.

[0009]US20170105493 discloses a link having two half-links and adjustment means comprising a screw passing through one of the half-links and cooperating with a threaded hole located in the other of the half-links to allow fine adjustment of the length of the link. This link has no actuator and no telescopic adjustment mechanism enabling to be set in at least two distinct indexed positions.

[0010]EP3795027 discloses an adjustable link comprising the features of the preamble to the independent claim.

BRIEF SUMMARY OF THE INVENTION

[0011]The aim of the present invention is to provide a length-adjustable link that is exempt from the above-mentioned disadvantages.

[0012]In particular, an aim of the present invention is to provide an adjustable link whose mechanism for adjusting its length is invisible from the outside of the link in order to improve the visual appearance of the bracelet.

[0013]Another aim of the present invention is to provide a link that allows the length of the bracelet to be easily adjusted when worn.

[0014]Another aim of the present invention is to provide an adjustable link that is less susceptible to dirt and build-up in its extended configuration.

[0015]An additional aim of the present invention is to provide a length-adjustable link which has a reduced number of parts in order to make it reliable and economical to produce.

[0016]These aims are achieved in particular by an adjustable link for bracelet, comprising a first and a second link element interconnected by a telescopic adjustment mechanism so as to be able to move in translation with respect to one another and to take up at least two separate indexed positions. The mechanism comprises an actuator accessible from the outside of the adjustable link, a lock rigidly attached to the actuator and arranged in a cavity of one of the first and second link elements, and an indexing member that is arranged to cooperate with the lock and that is rigidly attached to the other of the first and second link elements while extending in the direction of translation movement of the first link element with respect to the second link element. The first and second link elements are further configured to conceal the indexing member independently of whether they are in one or the other of said at least two indexed positions.

[0017]In an embodiment, the actuator is arranged on a face extending between two lateral sides of the adjustable link and accessible when the bracelet comprising the adjustable link is worn.

[0018]In an embodiment, one of the first and second link elements comprises a connecting body configured to slide in a housing of complementary shape, arranged in the other of the first and second link elements. The connecting body is further configured to conceal the indexing member therein independently of the indexed position selected.

[0019]In an embodiment, the contour of the housing is in contact with the corresponding contour of the connecting body independently of the indexed position selected.

[0020]In an embodiment, the mechanism further comprises additional coupling means for guiding the relative movement of the first and second link elements and/or for absorbing mechanical stresses between said first and second link elements.

[0021]In an embodiment, the additional coupling means are formed by at least one female element arranged within the connecting body of one of the first and second link elements, to receive a complementary male element rigidly connected to the other of the first and second link elements.

[0022]In an embodiment, the additional coupling means are arranged symmetrically with respect to a longitudinal axis of the indexing member.

[0023]In an embodiment, the actuator is in the form of a pusher arranged to move the lock from a locking position in which it is at rest and engaging with the indexing member, to an unlocking position in which the lock is actuated and no longer engages with the indexing member.

[0024]In an embodiment, the pusher is arranged to be actuated in an unlocking direction which is perpendicular to the direction of translational movement of the first link element relative to the second link element. The unlocking direction is more particularly perpendicular to the general plane of the adjustable link.

[0025]In an embodiment, the lock also comprises an opening arranged to receive a part of the indexing member.

[0026]In an embodiment, the lock is traversed from one side to the other by the indexing member when the link is in a retracted or partially retracted configuration.

[0027]In an embodiment, one of the first and second link elements comprises a fastening part. The latter comprises a central portion and two lateral portions arranged on either side of the central portion so as to form two gaps for receiving therein the lugs of a watch case or a fastening part of an adjacent link. The central portion comprises the cavity receiving the lock.

[0028]In an embodiment, the central portion also comprises a blind hole in the axial extension of the lock opening in order to receive the free end of the indexing member when the link is in a retracted or partially retracted configuration.

[0029]In an embodiment, the indexing member is in the form of a rod comprising at least one indexing element intended to cooperate with the lock.

[0030]In an embodiment, the indexing elements consist of two adjacent radial extensions providing three indexing positions.

[0031]In an embodiment, the indexing member is in the form of a notched bar comprising several notches intended to cooperate with the lock to lock the link in several indexed positions.

[0032]In an embodiment, the notched bar further comprises a longitudinal slot oriented in the direction of the translational movement. A stop is arranged inside the longitudinal slot to limit the relative movement between the first and second link elements.

[0033]In an embodiment, the lock comprises two blind holes arranged on either side of the opening. An elastic member is mounted in each hole. The elastic member is preferably a compression spring.

[0034]In an embodiment, the lock opening has a profile complementary to the indexing member to conform to the contour of a portion thereof when the link is in the retracted configuration.

[0035]In an embodiment, the indexing member is integrally rigid.

[0036]Another aspect of the invention relates to a wristwatch comprising at least one link according to any of the aforementioned embodiments. The actuator is disposed on the visible face of the watch bracelet when worn.

BRIEF DESCRIPTION OF THE FIGURES

[0037]Examples of embodiments of the invention are given in the description illustrated by the appended figures in which

[0038]FIG. 1 shows an exploded view of the adjustable link according a first embodiment;

[0039]FIG. 2 shows an exploded view of the adjustable link in a different orientation;

[0040]FIG. 3 shows a top view of the adjustable link in a retracted configuration;

[0041]FIG. 4 shows a side view of FIG. 3;

[0042]FIG. 5 shows a cross-sectional view of FIG. 3 along A-A;

[0043]FIG. 6 shows a cross-sectional view of FIG. 3 along B-B;

[0044]FIG. 7 shows a cross-sectional view of FIG. 4 along C-C;

[0045]FIG. 8 shows a top view of the adjustable link in an extended configuration;

[0046]FIG. 9 shows a side view of FIG. 8;

[0047]FIG. 10 shows a cross-sectional view of FIG. 8 along A-A;

[0048]FIG. 11 shows a cross-sectional view of FIG. 8 along B-B;

[0049]FIG. 12 shows a cross-sectional view of FIG. 9 along C-C;

[0050]FIGS. 13a to 13d show different cross-sectional views of the adjustable link according to a first sequence of manipulations to bring the link from a retracted configuration to an intermediate indexed position, in which the link has been lengthened by one millimetre with respect to its retracted configuration;

[0051]FIGS. 14a to 14c show different cross-sectional views of the adjustable link according to a second sequence of manipulations to bring the link from the intermediate indexed position to the extended configuration, in which the link has been lengthened by two millimetres with respect to its retracted configuration;

[0052]FIG. 15 shows an exploded view of the adjustable link according to a second embodiment;

[0053]FIG. 16 shows an exploded view of the adjustable link of FIG. 15 in a different orientation;

[0054]FIG. 17 shows a cross-sectional view along the length of the link when it is in a retracted configuration;

[0055]FIG. 18 shows a cross-sectional view of the link in the plane of the link when it is in a retracted configuration;

[0056]FIG. 19 shows a cross-sectional view similar to FIG. 17 when the link is in an intermediate position;

[0057]FIG. 20 shows a cross-sectional view similar to FIG. 18 when the link is in an extended configuration, and

[0058]FIG. 21 illustrates a cross-sectional view similar to FIG. 17 when the link is in an extended configuration.

EXAMPLES OF EMBODIMENTS OF THE INVENTION

[0059]In a first embodiment and with reference to FIGS. 1 to 2, the adjustable link 10 comprises a first and a second link element 20, 50 interconnected so as to be movable relative to one another in translation so that the link 10 can move from a retracted configuration to an extended configuration to adjust the length of the link.

[0060]According to an advantageous embodiment, the link 10 can be adapted so that it can be locked in at least one intermediate position between the retracted position and the extended position. This allows fine adjustment for comfort to be made to the bracelet incorporating the adjustable link, since the circumference of the bracelet can be increased by a first value when the link moves from the retracted configuration to the intermediate position, and by a second value when the link moves from the intermediate position to the extended configuration. The first and second values may, for example, be of the order of one millimetre and two millimetres respectively.

[0061]To this end, the first link element 20 comprises a locking/unlocking system and the second link element 50 has a rigid indexing rod 58 extending in the direction of translation of the first and second link elements 20, 50. The locking/unlocking system cooperates with the indexing rod 58 so as to be able to lock the first link element 20 relative to the second link element 50 in at least two indexed positions corresponding to the retracted configuration and to the extended configuration of the link.

[0062]This system comprises an actuator 28 typically arranged on a face extending between two lateral sides of the adjustable link 10 and accessible when the bracelet comprising the adjustable link is worn. The actuator 28 is in this example in the form of a pusher 28. The latter comprises a lock 30 provided with an opening 32, preferably circular, arranged to receive therein a segment of the indexing rod 58 when the link is in the retracted configuration as illustrated in FIG. 5. The pusher 28 and the lock 30 are in one piece in this example but could also comprise two separate parts rigidly connected together according to a variant.

[0063]The lock 30 generates its locking action in particular by means of a locking element 34 arranged to cooperate with the indexing rod 58 so that the latter is locked in translation when the link 10 is in the retracted configuration or in the intermediate position. This lock 30 is arranged in a cavity 26 located at a central portion 24 of a fastening part 22. Two blind holes 36 (FIG. 6) are made in the lock 30 on either side of the opening 32. An elastic member in the form of a compression spring 38, for example, is arranged in each hole in order to exert a return force urging the pusher 28 into a rest position. Other return means can be used, in particular by arranging a spring rod or leaf spring in the bottom of the cavity in order to urge the lock and therefore the pusher into its rest position.

[0064]Depending on whether the adjustable link 10 is in the retracted configuration shown in FIG. 5, in the extended configuration shown in FIG. 10 or in the intermediate position shown in FIG. 13d, the indexing rod 58 is always engaged, at least in part, in the opening of the lock 30 holding the latter in the cavity 26.

[0065]In view of FIGS. 3 and 4, the pusher 28 protrudes from the upper face of the first link element 20 when it is at rest. Pressing the pusher 28, in a direction orthogonal to the longitudinal axis of the indexing rod 58, brings its actuation face substantially at the level of the upper face of the central portion 24 of the first link element 20. According to a variant, the pusher is embedded in the body of the central portion when it is at rest.

[0066]The fastening part 22 comprises two lateral portions 40a, 40b arranged on either side of the central portion 24 so as to form two gaps 39 for receiving the lugs of a watch case (non-illustrated) or the fastening part of an adjacent link of the bracelet.

[0067]According to FIG. 1, the link 10 comprises guiding means, which will be described later, intended to guide the relative displacement of the first and second link elements 20, 50. The latter are configured to conceal the indexing member 58 and the guiding means independently of the indexed position of the first link element 20 relative to the second link element 50. This makes it possible to improve the aesthetics of a bracelet incorporating at least one link of this type compared with solutions of the prior art. For example, the first link element 20 may comprise for this purpose a connecting body 44 comprising an outer surface 44a visible from the outside of the link 10 when the latter is in the deployed configuration. The outer surface 44a is continuous in order to conceal the indexing member 58 and the guiding means whether the link is in its retracted, intermediate or extended configuration.

[0068]The connecting body 44 is arranged to slide inside a housing 57 of complementary shape of the second link element 50 inside which the indexing member 58 is located. In this example, the cross-section of the connecting body 44 is substantially rectangular, but other shapes may be envisaged according to alternative embodiments. The contour of the housing 57 is arranged with a functional play on the corresponding contour of the connecting body 44 independently of the retracted, intermediate and extended configurations of the link.

[0069]The indexing rod 58 may, for example, comprise a threaded part 61 screwed into the bottom of the housing 57 as illustrated in FIG. 5. The connecting body 44 comprises a passage 46, preferably cylindrical, which, on the one hand, extends from the cavity 26 receiving the lock 30 to a front face 45 of the connecting body 44 and, on the other hand, is aligned with the opening 32 of the lock 30 so that the latter can receive, through the opening 32, a segment of the indexing rod 58.

[0070]In view of FIG. 5, a blind hole 27, preferably cylindrical, is arranged in the central portion 24 of the fastening part. The blind hole 27 is arranged in the axial extension of the passage 46 and of the opening 32 of the lock 30 in order to receive therein the free end of the indexing rod 58 when the link 10 is in the retracted configuration. The indexing rod 58 therefore passes right through the lock 30 in this configuration.

[0071]The indexing rod 58 comprises, in this example, two radial extensions 60a, 60b which extend around the entire circumference of the indexing rod 58 so as to form a groove between the two extensions. The radial extensions may, however, extend over only part of the circumference of the indexing rod in a variant. The locking element 34 is in the form of a flange located at the lower part of the opening 32 of the lock 30 so as to come into abutment against one or other of the two radial extensions 60a, 60b. In the retracted configuration of the link illustrated in FIG. 5, the flange 34 is in abutment with the radial extension 60b, thus preventing any translation of the indexing rod 58.

[0072]Pressing the pusher 28 disengages the rim 34 from the radial extension 60b so that the link can be brought into the extended configuration shown in FIG. 10. A stop 48 is arranged at one end of the passage 46 to prevent the first and second link elements 20, 50 from disengaging from one another. The stop is in this example in the form of two pins arranged on either side of the indexing rod 58 to abut against the radial extension 60b.

[0073]Referring in particular to FIGS. 1, 2 and 12, the connecting body 44 comprises a first and a second guiding part 49a, 49b arranged symmetrically with respect to the passage 46. The second link element 50 comprises a first and a second complementary guiding part 68a, 68b arranged symmetrically with respect to the longitudinal axis of the indexing rod 58 so as to be able to move in translation inside the first and second guiding parts 49a, 49b respectively. In this example, the guiding parts of the connecting body 44 of the first link element 20 are in the form of holes 49a, 49b while the complementary guiding parts of the second link element 50 are in the form of rods.

[0074]These guiding means 49a, 49b, 68a, 68b also make it possible to absorb stresses, in particular torsional stresses, during handling of the link 10 in order to modify its length. The rods 68a, 68b have the advantage of guaranteeing functional play between the connecting body 44 of the first link element 20 and the housing 57 of the second link element 50 so that there is no friction between the connecting body 44 and the housing 57. This prevents the appearance of scratches on the surface 44a of the connecting body 44 which would be visible in the extended configuration of the link.

[0075]FIGS. 13a to 13d show a first sequence of manipulations to bring the link 10 from a retracted configuration to an intermediate indexed position. In the retracted configuration of the link shown in FIG. 13a, the locking element 34 of the lock is in abutment against the radial extension 60b preventing any translation of the indexing rod 58 of the second link element 50 relative to the lock of the first link element 20.

[0076]It is sufficient to press the pusher 28 in order to disengage the flange 34 from the radial extension 60b, then to impart a translational movement to the second link element 50 with respect to the first link 20 while maintaining pressure on the pusher 28 until the locking element 34 of the lock is at the level of a groove formed between the two radial extensions 60a, 60b. At this point, the pusher 28 is released so that the locking element 34 of the lock 30 engages in the groove, thus locking the link in the intermediate position between its retracted and extended configuration. The link has been lengthened in this example by about one millimetre.

[0077]FIGS. 14a to 14b show a second sequence of manipulations to bring the link from the intermediate position to the extended configuration. To do this, the pusher 28 is simply pressed again to release the flange 34 from the radial extension and then to impart a translational movement to the second link element 50 relative to the first link 20 while maintaining pressure on the pusher 28 until the locking element 34 of the lock is located on the other side of the radial extension 60a located close to the free end of the indexing rod 58. At this point, the pusher 28 is released so that the locking element 34 of the lock comes against the side of the radial extension 60a, thus locking the link in the extended configuration. The link has been lengthened in this example by about two millimetres compared with its retracted configuration.

[0078]According to another embodiment shown in FIGS. 15 to 21, the indexing rod is replaced by an indexing bar 58 comprising a notched part 62 and a fixing part 66 screwed against the bottom of the housing 57 of the second link element. The notched part 62 comprises several parallel grooves located preferably at regular intervals along the movement of the first link element 20 relative to the second link element 50 to lock the link in several indexed positions. The notched part preferably comprises three grooves 63a, 63b, 63c, intended to cooperate with the locking element 34 of the lock 30 to lock the link in three indexed positions corresponding respectively to the retracted, intermediate and extended configuration. Alternatively, these grooves could be replaced by holes or indentations of a different geometric shape.

[0079]The lock 30 comprises an opening 32 of oblong shape adapted to the shape of the notched part 62 so that the latter can pass right through the lock 30 when the link is in the retracted configuration as shown in FIG. 17. In this configuration, the end of the notched part 62 is housed in a blind hole 27, which may be rectangular in cross-section, located in the central portion 24 of the fastening part of the first link element.

[0080]With reference to FIGS. 18 and 21, the passage 46 extending from the cavity 26 to the front face of the connecting body 44 preferably has a rectangular cross-section. The notched bar 58, in particular its notched part 62, also has a slot or longitudinal aperture 64 inside which is mounted a stop, for example a pin 67, rigidly attached to the first link element 20. This pin makes it possible to limit the relative movement of the first and second link elements 20, 50 by preventing their disengagement when the link 10 is in the extended configuration as shown in FIG. 21.

[0081]The sequence of operations to be performed to adjust the length of the link remains the same as the one described with reference to the first embodiment. In its retracted configuration shown in FIG. 17, the locking element 34 of the lock is engaged in a first groove 63a located furthest away from the free end of the notched part. In this configuration, the stop 67 is arranged against an edge forming one of the distal ends of the longitudinal aperture 64 as shown in FIG. 18.

[0082]When the link is in the intermediate position as shown in FIG. 19, the locking element 34 of the lock is engaged in a second groove 63b adjacent to the first groove 63a and at a distance of approximately one millimetre therefrom.

[0083]When the link is in the extended position as shown in FIGS. 20-21, the locking element 34 of the lock is engaged in a third groove 63c located close to the free end of the notched part and distant from the first groove 63a by approximately two millimetres. According to this configuration, the stop 67 has moved relative to the second link element 50 along the longitudinal aperture 64 during the relative movement between the first and second link elements 20, 50 to end up against an opposite edge of the aperture in order to prevent disengagement between the first and second link elements.

[0084]As in the first embodiment, the connecting body 44 comprises a first and a second guiding part 49a, 49b arranged on either side of the passage 46. The second link element 50 comprises a first and a second complementary guiding part 68a, 68b arranged symmetrically with respect to the indexing bar 58 so as to be able to move in translation inside the first and second guiding parts 49a, 49b respectively.

[0085]The link 10 is intended to be integrated into a bracelet, in particular a watch bracelet, so that the pusher 28 is arranged on the visible side of the bracelet when it is being worn, which makes it easy to adjust the length of the bracelet when worn. The bracelet may comprise several adjustable links in order to increase the adjustment length.

[0086]Various modifications can be made to the adjustable link just described without departing from the invention as defined by the claims. For example, the pusher may be replaced by a knurled wheel with an integrated lock having a cylindrical aperture coaxial with the axis of rotation of the knurled wheel. A locking element similar to that described above is arranged in the opening so as to engage or not with the indexing member according to the two aforementioned embodiments depending on the angular position of the knurled wheel. According to another variant, the pusher could be replaced by a pull tab to actuate the lock not in a direction perpendicular to the plane of the bracelet but in a direction parallel to this plane towards a side edge of the link.