CH702524A2 - Clasp e.g. unfolding buckle clasp, for strap of timepiece, has retention housing located at distance from rotation axis, where retention housing is cooperated with fixation barret fixed at one of ends of strap - Google Patents

Abstract

The clasp (1) has an adjusting device for adjusting effective length of a strap, where the adjusting device has two mobile units (12) movable between a short position and a long position. A frame (3) has lateral posts (4) on which one of the mobile units is mounted so that the mobile unit is pivoted in reference to a rotation axis (X1). Each mobile unit has a retention housing (16) located at a distance from the rotation axis, where the retention housing is cooperated with a fixation barret (18) fixed at one of ends of the strap.

Description

Technical area

The present invention relates to a clasp for a timepiece bracelet of the type comprising first and second ends, the clasp comprising a device for adjusting the useful length of the bracelet comprising two movable members between at least a first position, short, and a second position, long.

State of the art

Many bracelet clasps for adjusting the useful length of the bracelet are known, especially in the field of belts.

In the field of belts, the devices of the state of the art generally provide for translational movement of a first end of the belt relative to the second end held fixed in the clasp. These devices, however, have complex kinematic mechanisms that are difficult to transpose to the field of clasps wristbands, especially for congestion issues.

An example of such a device is described in EP 1 860 969 B1.

In the field of watchmaking, devices for adjusting the useful length of the bracelet are also known but they are generally implemented in clasps of the clasp type.

Patent CH 663 522 A5 discloses a folding clasp with two James pivoted relative to each other to increase the length of the bracelet when deployed and define its useful length, shorter, when they are folded one over the other. This document proposes to add a short link between the two blades, the one being also pivotable relative to one and the other of the two blades. Thus, this link may be arranged either substantially in alignment with a first blade to define a first length of the bracelet, or substantially in alignment with the second blade to define a second length of the bracelet.

However, this device has a number of practical disadvantages, including the fact that the maintenance of the set position is not ensured when the clasp is open. In addition, the addition of the link that can not be placed in perfect alignment with either of the two blades, in either of its positions, induces a local extra thickness of the clasp located on the wrist side of the wearer of the bracelet, thereby degrading the comfort of wearing the clasp.

To solve these problems in particular, several devices have been proposed in connection with clasps comprising a hood for concealing a more comfortable mechanism but also more complex.

The patent application EP 1 378 185 A1 provides an example of such a device, wherein a member secured to one end of the bracelet can be moved in translation on the inside of the cover to adjust the useful length of the bracelet .

Patent EP 0 819 391 B1 provides an example of such a device comprising two specific end links housed in the cover of the clasp. A first of these links is rotatably mounted in the hood via a conventional strap attachment bar, while the second link is rotatably mounted on the first link. The two links having respective shapes such as the first link can be inserted, by rotation, in the second link, or in an additional intermediate element, to shorten the length of the bracelet. The two links are located in the extension of one another in the elongate adjustment position.

However, all these devices are of little practical interest when it comes to adjust the useful length of a bracelet with flexible strands, for example leather, associated with a discreet clasp, including the type pin. Indeed, in the last document mentioned above, for example, the specific shape of the second link gives it a particular aesthetic, not compatible with the aesthetic standards of high-end products and, making it preferable to hide it in the hood of the clasp.

Disclosure of the invention

A main object of the present invention is to provide a discreet clasp to perform an adjustment of the useful length of the bracelet in a simple and effective manner.

For this purpose, the present invention relates more particularly to a clasp of the type mentioned above, characterized in that it comprises a frame having two lateral uprights on each of which is mounted one of the movable members, so as to that the latter can pivot with reference to a first axis of rotation, and in that each of the movable members comprises a retaining housing, located at a distance from the first axis of rotation and intended to cooperate with a lug of the one end of the bracelet.

With these features, a conventional bracelet can be linked to the clasp, without having to give up the implementation of a fine adjustment device of its length.

Advantageously, the clasp comprises at least one movable locking member between a first open position, in which the movable members are free to pivot, and a second position, closed, in which at least one of the members mobile is locked.

More particularly, it can be provided that each of the movable members is integral with a stabilizing member having first and second locking surfaces, opposite one another with respect to the first axis of rotation and, arranged to cooperate with the locking member, respectively, in the short position and in the long position.

Thus, the stability of the desired adjustment position is ensured whatever the state, open or closed, of the corresponding clasp.

According to an advantageous embodiment, one can further provide that each of the movable members is integral with a polarizing member arranged to cooperate with a positioning pin, integral with the corresponding lateral amount, to substantially limit to 180 degrees, in one way or the other, the pivoting of the movable member.

Thanks to these features, the precise location of the service positions is ensured while in addition the two pins of the strap of the strap are necessarily driven in the same direction of rotation about the first axis of rotation during changes position, thus avoiding twisting the bar.

In addition, preferably, two recesses are arranged integrally with each of the lateral uprights and symmetrically with reference to the first axis of rotation to receive one of the two pins of the bracelet of the fastening bar, respectively, in the position short and in the long position.

These recesses allow the user of the clasp to feel when the bar reaches one of the service positions, during changes in the length of the bracelet, and gives a feeling of high quality.

According to a preferred embodiment, the clasp comprises two locking members associated respectively with a first and second lateral upright, each of the locking members comprising a slide arranged in a slot in the corresponding lateral upright, in one direction. which is substantially in the extension of the direction of the bracelet.

In particular, it is also possible that each of the slides is secured to an axis with a pin of the clasp for cooperating with holes in the second end of the bracelet.

According to a preferred embodiment, each of the lateral uprights comprises a substantially cylindrical housing in which is housed one of the movable members. In addition, each movable member may then have a generally cylindrical shape comprising a substantially cylindrical recess, open in the cylindrical side wall of the movable member and of diameter less than the radius of the latter, to define the retaining housing of the bar of fastening the bracelet.

Furthermore, each of the locking members may have a third extraction position, intended to allow extraction of the strap of the bracelet by passing its pivots in adapted recesses formed in the lateral flank of each of the lateral amounts. These features allow an easy change of bracelet.

The clasp mentioned above can take different forms, such as being of the loop type with buckle or the type of folding clasp, without departing from the scope of the present invention.

Brief description of the drawings

Other features and advantages of the present invention will appear more clearly on reading the detailed description of a preferred embodiment which follows, with reference to the accompanying drawings given by way of non-limiting examples and in which :

- figs. 1a, 1b, 1c and 1represent perspective views of a clasp according to a preferred embodiment of the present invention, in four different respective configurations;

[0029] - FIG. 2 is an exploded perspective view, partly in section, of the clasp in its configuration of FIG. 1b;

[0030] - FIG. 3 shows a simplified sectional view of a first construction detail of the clasp, in its configuration of FIG. 1 C;

- fig. 4 shows a simplified sectional view of a second construction detail of the clasp, in its configuration of FIG. 1c, and

[0032] - FIG. 5 shows a simplified sectional view of a third construction detail of the clasp, in its configuration of FIG. 1 C.

Mode (s) of realization of the invention

Figs. 1a, 1b, 1c and 1represent perspective views of a clasp 1 according to a preferred embodiment of the present invention, in four different respective configurations.

The clasp 1 is of the buckle type with pin 2, by way of non-limiting illustration. Specifically, the pin 2 is double here, for mainly aesthetic reasons and independent of the implementation of the present invention.

The barb is pivotally mounted in a hoop 3 of the generally U-shaped clasp, specifically in first and second lateral uprights 4 of the hoop, via an axis or tube 5 (Fig. 2) in which are screwed two screws 6 whose heads cooperate with slides or plates 8 engaged in slots 9 of the lateral uprights.

Furthermore, each lateral upright 4 comprises a cylindrical housing 10 (FIG 2) in which is arranged a cylindrical movable member 12, performing the function of a drum as will be explained later, retained in its housing by a stabilizing member, here having the shape of a rivet 13 whose head 14 cooperates with the outer face of the corresponding lateral upright. The two sets rivet-drum associated with the two lateral uprights are aligned along an axis of rotation X1.

One can optionally provide at least one laser welding point, or other means of equivalent connection, between each movable member 12 and the rivet 13 corresponding, after assembly, to avoid any loss of mutual orientation.

Each movable member comprises a recess, open in its cylindrical side wall and of diameter less than its radius, to define a retaining housing 16 (FIG 2) for a pivot 17 (FIG 2) of a bar 18 fixing the bracelet.

FIG. 1a represents the clasp in its long configuration, while the barb 2 is folded down.

In this configuration, the movable members 12 are oriented such that the bar 18 is in a position remote from the base 20 of the arch 3.

FIG. 1b represents the clasp in its short configuration, while the barb 2 is folded.

In this configuration, the movable members 12 are oriented such that the bar 18 is in a position close to the base 20 of the arch 3.

To go from the configuration of FIG. 1a to that of fig. 1b, the movable members 12 perform a rotation of axis X1 of 180 degrees.

It also emerges from these figures that the head 14 of each rivet 13 has two notches 22 diametrically opposed and each fulfilling the function of a locking surface arranged to cooperate with a finger 23 secured to the corresponding plate 8, that thus playing the role of a locking member.

Indeed, in the configurations of FIGS. 1aet 1b, each finger 23 is engaged in one of the notches 22 of the corresponding rivet 13, thus preventing the latter from turning on itself.

Therefore, in these configurations, the two movable members 12 are locked and the useful length of the bracelet is kept fixed.

By examining FIG. 1c, it can be seen that, when the bracelet strand intended to cooperate with the barb is not in place, each plate 8 can slide in its slot 9, in the direction of the base 20 of the arch, to release the finger 23 of the corresponding notch 22 and thus release the movable members 12.

Therefore, in the configuration of FIG. 1c, the movable members 12 are free to rotate, with respect to the axis X1, to move from the short configuration, shown, to the long configuration, as illustrated in FIG. 1a. The plates 8 can then be moved away from the base 20 of the arch to ensure the locking of the rivets 13 by means of the fingers 23.

FIG. 1d illustrates a preferred variant of the present invention. According to this variant, the plates 8 may be closer to the base 20 of the arch than in the configuration of FIG. 1c to provide access to a recess 24 formed in each inner flank 25 of each lateral upright. The recess 24 communicates on the one hand with the slot 9 and on the other hand with the underside of the corresponding lateral upright.

In the configuration of FIG. 1d, the bar 18 can be easily extracted from the clasp 1 in particular to make a bracelet change. Indeed, it appears clearly from fig. 1d that, to extract the bar 18 out of the clasp 1, it is sufficient to move it, in a first step, in the slot 9 towards the base 20 of the arch, then down through the recess 24 .

The establishment of a new bracelet assembled to its own bar 18 (or possibly to the same bar) is performed by following the reverse path.

Different means may be provided to allow the displacement of the wafers 8 without departing from the scope of the present invention. The user can, for example, grab the pads between two fingers and move them directly, or he can grab the pin 2 to move the axis in the direction of the slot 9, after having raised.

It will also be noted that the plates 8 are not necessarily integral with the tube 5 carrying the barb. The tube 5 could be fixed in this case with respect to the hoop 3.

FIG. 2 shows an exploded perspective view of the clasp in its configuration of FIG. 1b, in which the lower right portion is shown in partial section along a horizontal median cutting plane.

It appears from FIG. 2que each rivet 13 comprises two portions juxtaposed between its head 14 and its foot engaged in the corresponding movable member 12.

On the one hand, the rivet includes a bearing 26 intended to be engaged in a washer 28 and ensuring the proper positioning of the corresponding movable member in the direction of the axis X1.

On the other hand, the rivet also comprises a polarizer 29 arranged between the span 26 and the head 14, whose function will be explained in detail in connection with the detailed description of FIG. 5.

Each washer 28 has a locating pin 30 on one of its faces, outer, and two recesses 32 on the other side, internal. The positioning pin 30 is arranged in particular to cooperate with a milling 33 (FIG 5) made in the corresponding lateral amount 4 to ensure a correct orientation of the washer 28 relative to the frame of the clasp, that is to say his hoop 3.

The recesses 32 define the positions of the pivots 17 of the bar 18 for fixing the bracelet, respectively, in one and the other of its positions, short and long. Thus, when the movable members 12 are free to rotate, each pivot 17 is disengaged from a recess 32, under the action of the user of the clasp and by compression of the springs 34 arranged in the bar 18, then slides on the inner face of the washer 28 before lodging in the other recess 32 by decompression of the springs 34.

It is also apparent from FIG. 2que each plate 8 is integral with a gun composed of two juxtaposed portions 36 and 37 having substantially different diameters. At the same time, it appears more particularly from the sectional part of FIG. 2 that each slot 9 comprises two juxtaposed portions 38 and 39 in the longitudinal direction of the corresponding lateral upright and whose widths are substantially different. One of the portions 36 of the barrel is fitted into the narrower portion 38 of the slot 9 to generate friction, while the other portion 37 of the barrel has a diameter slightly less than the width of the other portion 39 of the barrel. slot 9 to ensure a low guiding, substantially frictionless.

FIG. 3 shows a construction detail of the clasp of FIG. 2, the section being made in a plane oriented in the longitudinal direction of a lateral upright and located at the portion 38 of the corresponding slot 9.

It is noted in FIG. 3que, advantageously not limiting, the walls of the slot 9 are not rectilinear at the portion 38. Indeed, each side of the slot has two small constrictions 40 to define the three different positions of the wafer as they have been described above. Thus, the portions 36 of the barrel and 38 of the slot both have a slight elastic deformation, when the plate is moved from one of its three positions to another, defining a slight sensation of notching for the user.

Figs. 4 and 5 show sectional views, respectively along the plane indicated by the line IV-IV in FIG. 3 and the plane indicated by the line V-V in fig. 4, additional details of construction of the clasp of FIG. 2.

It appears from FIG. 4que, in the unlocked position, the finger 23 is out of reach of the head 14 of the rivet 13 which can then rotate.

The bar 18 has been shown schematically in FIG. 4 while its pivots 17 are housed in recesses 32 of the washers 28. However, the bar is illustrated in its configuration at rest, that is to say when the springs 34 are not compressed under the effect of a external intervention. Thus, it is noted, as an indication, that the springs 34 have a slight prestressing even when the pivots 17 are housed in recesses 32.

FIG. 5 illustrates more clearly the respective shapes of the positioning pin 30 and the polarizer 29, as well as their mode of cooperation.

The polarizer 29 has, in section, substantially a general shape of mushroom whose foot has dimensions allowing it to be out of reach of the positioning pin, while the cap has dimensions greater than those of the foot and lead its cooperation with the positioning pin in some cases.

In this case, FIG. 5illustrates the clasp in its short position and it is found that to move to the long position, it is necessary that the polarizer 29, so the movable member 12 which it is integral, rotates in the direction of rotation anti-clockwise. Clockwise rotation is not possible here. After having traveled at a 180 degree angle, the other side of the mushroom cap comes into abutment against the positioning pin 30. Of course, at the same time, the pivots 17 of the fixing bar pass from a pair of 32 digs to the next.

Such an arrangement allows, on the one hand, to identify the operating positions of the movable members, in which the fixing bar is positioned correctly, that is to say substantially in the extension of the bracelet. On the other hand, this arrangement further ensures that the two movable members rotate in the same direction at each new setting of the length of the bracelet, which prevents the bar 18 to be twisted and ensures the latter a greater longevity .

Returning to FIG. 2, it will be noted that the bar 18 for fastening the bracelet carries two spacers 42, these being implemented by way of nonlimiting illustration, not only for aesthetic reasons but also for technical reasons.

Indeed, one can advantageously provide that at least one of the spacers 42 is adjusted on the bar 18 with a predefined friction level when it is moved along the bar. Such a measure ensures the maintenance of the bar 18 at the end of the bracelet during a bracelet change, as an alternative to an adjustment on the bar of its housing formed in the end of the bracelet.

The foregoing description attempts to describe a particular embodiment by way of non-limiting illustration and, the invention is not limited to the implementation of certain particular features which have just been described, as for example the fact that the pin 2 is double or the shape of the plates 8.

The skilled person will not encounter any particular difficulty to adapt the content of the present disclosure to his own needs and implement a clasp for a timepiece bracelet in part to meet the characteristics that have just been presented without departing from the scope of the present invention.

It will be noted for example that the washers 28 may be omitted because their recesses 32 do not ensure, alone, the positioning of the bar 18 for fixing the bracelet. In this case, a specific positioning pin can be provided in each lateral upright. It should also be noted that even if the quality of the felt in handling would suffer, it is possible to provide only one positioning pin in a single lateral upright, without departing from the scope of the invention. Likewise, a single locking member is sufficient to fulfill the desired function. It is also understood that the movable members could rotate in opposite directions with respect to what has been described, without departing from the scope of the invention, the positioning pin then being placed differently, but adequately with respect to the polarizer integral with each movable member.

In the embodiment that has been described, it is expected that the friction occurring between the slot 9 and the plates 8 ensures the maintenance of these in current use of the clasp 1. However, different alternatives are possible for ensure the maintenance of the pads 8 in their locking position, without departing from the scope of the invention. In particular, it is possible for the barb to be secured to a specific locking member to prevent its translation, such as for example a polarizer that can slide in a slot only when the inclination of the barb corresponds to a predefined value. Alternatively, it can be provided that springs are arranged between the wafers in such a way that they can be brought closer to each other while simultaneously being extracted from a notch to allow their translation into the slot 9, response to simultaneous pressure exerted by a user on both platelets. In this case, of course, the pads may be integral or not of the barb.

Furthermore, it will be recalled that the clasp according to the present invention is not limited to a clasp type buckle with barb. Those skilled in the art may in fact adapt the content of the present disclosure to implement a clasp, for example, with a folding clasp whose end includes the characteristics of the invention without departing from the scope thereof.

Claims (12)

1. Clasp (1) for a timepiece bracelet of the type comprising first and second ends, the clasp comprising a device for adjusting the useful length of the bracelet comprising two movable members (12) between at least a first position, short, and a second position, long, characterized in that it comprises a frame (3) having two lateral uprights (4) on each of which is mounted one of said movable members, so that the latter can rotate in reference to a first axis of rotation (X1), and in that each of said movable members (12) comprises a retaining housing (16) located at a distance from said first axis of rotation (X1) and intended to cooperate with a bar (18) fixing one of the ends of the bracelet. 2. Clasp (1) according to claim 1, characterized in that it comprises at least one locking member (8, 23) movable between a first open position, wherein said movable members (12) are free to pivot, and a second closed position in which at least one of said movable members is locked. 3. Clasp (1) according to claim 2, characterized in that each of said movable members (12) is integral with a stabilizing member (13) having first and second locking surfaces (22), opposite one by relative to each other with reference to said first axis of rotation (X1) and arranged to cooperate with said locking member (8, 23), respectively, in the short position and in the long position. 4. Clasp (1) according to claim 3, characterized in that each of said movable members (12) is integral with a polarizing member (29) arranged to cooperate with a locating pin (30), integral with said lateral upright (4). ) corresponding, to limit substantially to 180 degrees, in one direction or the other, the pivoting of the movable member (12). 5. Clasp (1) according to claim 4, characterized in that two recesses (32) are arranged integrally with each of said lateral uprights (4) and symmetrically with reference to said first axis of rotation (X1) to receive a pivot (17) of the bar (18) for fixing the bracelet, respectively, in the short position and in the long position. 6. Clasp (1) according to any one of claims 2 to 5, characterized in that it comprises two locking members (8, 23) associated respectively to the first and second lateral uprights (4), each of the organs of locking comprising a slide (8) arranged in a slot (9) formed in the corresponding lateral upright, in a direction which is substantially in the extension of the direction of the bracelet. 7. Clasp (1) according to claim 6, characterized in that each of said slots (9) has at least one throat (40) in the direction of its width to define the positions of the slide (8) corresponding to defining a notching. 8. Clasp (1) according to any one of claims 6 or 7, characterized in that each of said slides (8) is integral with an axis (5) carrying at least one barb (2). 9. Clasp (1) according to any one of the preceding claims, characterized in that each of said lateral uprights (4) comprises a substantially cylindrical housing (10) in which is housed one of said movable members (12). 10. Clasp (1) according to claim 9, characterized in that each movable member (12) has a generally cylindrical shape comprising a recess, open in the cylindrical side wall of said movable member and less than the radius of the latter, for define said retaining housing (16) of the bar (18) for fixing the bracelet. 11. Clasp (1) according to any one of claims 2 to 10, characterized in that each of said locking members (8, 23) has a third extraction position, intended to allow extraction of the bar (18). ) fastening the bracelet by passing its pivots (17) in recesses (24) adapted formed in the inner side (25) of each of said lateral uprights (4). 12. Bracelet for timepiece comprising a clasp (1) according to one of the preceding claims.