EP0350785B1 - Extensible, fine adjustable wrist-strap fastener - Google Patents

Description

The present invention relates to a bracelet clasp comprising a first element attached to one end of the bracelet and a second element attached to the other end of the bracelet, the bracelet being composed of articulated links each having a substantially identical width, said width being taken in the longitudinal direction of the bracelet, the first and second elements cooperating with each other to ensure the closure of the clasp by superimposition of said elements, the first element carrying a hook provided with a spout directed perpendicularly to the longitudinal direction of the bracelet and the second element being pierced with at least one opening into which the hook can be inserted, a trigger being mounted captive under said second element and sliding relative to it, the trigger having a portion emerging laterally from said second element under the action of spring return, said servan portion t of a push button which can be actuated by a finger to move the trigger against the action of the spring, said trigger being equipped with a first hole offset partially with respect to the opening of the second element so that , when the hook is inserted into the opening of the second element, it then engages in the hole in the trigger and gradually moves it against the action of the spring until the hook's beak passes under the trigger and locks the first element on the second, said trigger being displaceable by pressing the finger on the push button to align said opening with said first hole and thus allow the opening of the clasp.

A clasp corresponding to the generic definition which has just been given is described in the document CH-A-568 035 (= US-A-3 913 182). This clasp, developed in particular for a watch strap, has two rigid elements attached to the free ends of the strap. One of the elements has a hook which can be inserted into an opening carried by the other element. This other element has a trigger arranged to lock the hook when the elements are pressed one on the other. The trigger has a push button emerging from the other element which, when pressed with a finger, unlocks the elements and opens the clasp.

A clasp having a lot of analogy with that described above is described in document DE-A-35 20 122. In addition to the locking system using a hook and a trigger arranged as above, the clasp offers the possibility of s 'extend beyond the simple extension caused by the opening of two blades hinged one on the other and this thanks to the fact that one of the blades is slidably mounted in a bracket itself hinged on the other blade.

The document CH-A-553 553 describes a clasp allowing the shortening or lengthening of a bracelet. For this purpose, it is provided with a movable plate sliding under a fixed plate, each of the plates being equipped with holes superimposed in pairs. A pair of holes can penetrate a hook, the beak of which is arranged in the longitudinal direction of the bracelet. To open the clasp, press a button in the longitudinal direction of the bracelet. This construction therefore in no way adapts to the clasp of the invention. In addition, this construction in no way contemplates a fine adjustment, but a coarse adjustment extending at least over the width of a link.

However, none of the documents cited offers the possibility of shortening or lengthening somewhat the length of the bracelet to allow this bracelet to be worn tight or loose around the arm that carries it. However, it is found that there is often a need to make such an adjustment, because the dimensions of the arm change depending on whether the ambient temperature is low or high. Without possible adjustment, the bracelet can strangle the wrist in hot summer temperatures. Conversely, in winter, this same bracelet is free around the wrist and if it is used to attach a watch, the latter may take undesirable positions, for example that of being under the wrist. It has also been found that the difference between the dimensions of an inflated or narrowed wrist of the same person is less than the usual width of the links making up the bracelet. It follows from this that adding or removing a normal link from the bracelet is not entirely satisfactory. Some manufacturers offer half links for this, a solution that is not very aesthetic, expensive and difficult to implement by the wearer of the bracelet.

To overcome the drawbacks listed above, the present invention provides a clasp which makes it possible to easily adapt a bracelet to the member who wears it. To do this, the clasp meeting the generic definition given in the preamble to this description is characterized by the fact that the trigger is equipped with a second hole identical to the first and placed next to and near it in the direction of the longitudinal direction. of the bracelet, the distance separating the holes being less than the width of a link, the hook can then be introduced into the first or second hole depending on whether one wishes a tight or loose winding of the bracelet around the member who wears it .

• la figure 1 est une vue en perspective du fermoir selon l'invention,
• les figures 2a, 2b et 2c montrent une coupe opérée selon la ligne II-II de la figure 1 dans trois situations différentes selon la position du crochet par rapport à l'élément sur lequel il vient se verrouiller.
• la figure 3a est une coupe opérée selon la ligne III-III de la figure 1 et
• la figure 3b est une coupe opérée selon la ligne III-III de la figure 1 et selon un mode d'exécution différent de celui montré en figure 3a.

The invention will now be described in the description which will follow with the aid of the drawing which illustrates it by way of example and in which:

• FIG. 1 is a perspective view of the clasp according to the invention,
• Figures 2a, 2b and 2c show a section made along the line II-II of Figure 1 in three different situations depending on the position of the hook relative to the element on which it is locked.
• FIG. 3a is a section made along the line III-III of FIG. 1 and
• Figure 3b is a section along the line III-III of Figure 1 and according to a different embodiment from that shown in Figure 3a.

Figure 1 is an enlarged perspective view of the bracelet clasp according to the invention. This clasp comprises a first element 1 attached to one of the ends 2 of the bracelet 3. This first element 1 carries a hook 4 capable of a spout 5, said spout being directed perpendicular to the longitudinal direction of the bracelet. The clasp also has a second element 6 attached to the other end 7 of the bracelet 3. This second element 6 is pierced with at least one opening 8 into which the hook 4 can penetrate. Under the second element 6 is mounted a trigger 9. This trigger is slidably mounted under the element 6 and is held captive there by means which will be discussed below. The trigger 9 also has a portion 10 which emerges laterally from the second element under the return action of a spring 12 not shown here, but which appears in Figures 2a to 2c. This portion 10 serves as a push button which can be actuated by a finger, in the direction of the arrow A, to move the trigger against the action or spring. The trigger is also equipped with a first hole 11. As FIG. 1 and FIG. 2a (which is a section along the line II-II of FIG. 1) clearly show it, the first hole 11 is partially offset with respect to the opening 8 made in the second element 6.

Figures 2a to 2c describe the operation of the clasp as is known from the prior art contained in the documents cited above. FIG. 2a shows the open clasp as it also appears in FIG. 1. Here the trigger 9 is pushed towards the outside of the element 6 by the action of the compression spring 12. FIG. 2b shows that the hook 4 of element 1 was introduced into the opening 8 of element 6 and, by the rounding located under the spout 5, it moved the trigger 9 to the left, against the action of the spring 12 which is then almost entirely compressed. By finishing introducing the hook 4 into the opening 8 and the hole 11, we then find the situation presented in FIG. 2c where the spout 5 of the hook is located under the trigger 9 so that the element 1 is locked on the element 6, the trigger then resuming the position it had in FIG. 2a by the detent action of the spring 12. To open the clasp, it will then suffice to press with a finger on the trigger 9 via of the push button 10, in the direction of the arrow A, to find the situation of FIG. 2b, situation for which the element 1 can be separated from the element 6.

Two remarks can be made here concerning the details of the mechanism presented.

The first remark concerns the trigger 9 which must be provided with means preventing it from escaping from the element 6. FIG. 2a shows a possible means for achieving this goal. A slightly longer groove 13 is made in the trigger than the length of the excursion required by the trigger to fulfill its role. A screw 14 is placed in the bottom wall 15 completing the element 6, the end of the screw 14 plunging into the groove 13.

The second remark concerns the way in which the trigger 9 is held sliding and trapped under the element 6. In all the figures presented, the element 6 comprising the opening 8 is part of a tube comprising, inter alia, a lower wall 15 and a closure 16 at one end of the tube. The trigger is thus slidably mounted and is trapped in the tube in question. One could however imagine other solutions. That for example which would consist in practicing under the element 6 two slides in dovetails, these slides receiving the trigger provided, for its part, with lateral edges conforming to the shape of the slides to maintain said sliding and captive trigger under the element 6.

According to an essential character of the invention and as can be seen in FIG. 1 and in FIGS. 3a and 3b which are sections along the line III-III of FIG. 1, the trigger 9 is equipped with a second hole 17, identical to the first 11 and placed next to it in the direction of the longitudinal direction of the bracelet. Thus, the hook 4 may be introduced into the first hole 11 (FIG. 3a) or the second hole 17 (FIG. 3b) depending on whether a tight or loose winding of the bracelet is respectively desired around the wrist. It can be seen that the holes 11 and 17 are relatively close to each other, this generally compensating for the increase in the perimeter of the wrist in hot weather. In hot weather, the hook is introduced into the hole 17 and in cold weather, into the hole 11. This ensures easy wearing of the bracelet in all circumstances.

Figure 3a shows that the opening 8 is unique and that it gives access to both the two holes 11 and 17 carried by the trigger 9. Figure 3b shows a different embodiment of the element 6 which here comprises two separate openings 18 and 19 giving access respectively to the first 11 and second 17 holes drilled in the trigger 9. In certain circumstances, this other embodiment can facilitate the introduction of the hook into the desired hole.

Returning to FIG. 1, it can be seen that the first element 1 is attached, in addition to the end 2 of the bracelet 3, a first arm 20 and that the second element 6 is attached, in addition to the end 7 of the bracelet 3, a second arm 21. The free ends of the arms 20 and 21 are joined together by means of a hinge 22. We are dealing here with a clasp with a folding clasp, a loop well known in the state of the art. So that this type of clasp can accommodate the length adjustment which is the main object of the present invention, it is necessary that one of the arms 20 or 21 can be shortened, or lengthened depending on whether the hook 4 is introduced respectively into the first or second hole carried by the trigger.

The solution adopted in FIG. 1 consists in making the second arm 21 adjustable. The arm comprises a first blade 23, one of the ends of which carries the hinge 22, and a second blade 24 provided with opposite slides 25 and in which the first is engaged. blade 23. The second blade 24 is attached to the second element 6. To limit the travel of one blade relative to the other, a device is provided comprising a screw 26 with nut, the latter being engaged in a groove 27, the length is limited.

It is obvious that the clasp of the invention is not limited to the use of the folding clasp formed by the arms 20 and 21, the elements 1 and 6 being able to be attached only to the ends of the bracelet.

Claims (5)

1. Bracelet clasp including a first element (1) attached to one end (2) of the bracelet (3) and a second element (6) attached to the other end (7) of the bracelet (3), the bracelet comprising articulated links each exhibiting a substantially similar width, said width being taken in the longitudinal direction of the bracelet, the first and second elements cooperating to assure latching of the clasp by superposition of said elements, the first element bearing a hook (4) provided with a beak (5) directed perpendicular to the longitudinal direction of the bracelet and the second element being pierced with at least one opening (8) into which the hook may be introduced, a catch (9) being captively mounted under the second element and slidable relative thereto, the catch exhibiting a portion (10) emerging laterally from said second element under the return force of a spring (12), said portion serving as a push button adapted to be operated by a finger so as to displace the catch against the spring action, said catch being provided with a first hole (11) partially set off relative to the opening in the second element so that when the hook is introduced into the opening of the second element it then engages with the hole of the catch so as to displace said catch gradually against the action of the spring until the beak of the hook passes under the catch and latches the first element to the second element, said catch being displacable by finger pressure on the push button so as to align said opening with said first hole thus to permit opening of the clasp, characterized by the fact that the catch is provided with a second hole (17) identical to the first hole and placed beside and close to said first hole in the longitudinal sense of the bracelet, the distance separating the holes being less than the width of one link, the hook thus being capable of introduction into the first or the second hole in accordance with whether the bracelet is to embrace tightly or loosely the member bearing it.
2. Clasp according to claim 1, characterized by the fact that the second element (6) includes a single opening (8) giving access to the first (4) and second (17) holes borne by the catch (9).
3. Clasp according to claim 1, characterized by the fact that the second element (6) includes first (18) and second (19) openings arranged side by side, said first and second openings giving access respectively to the first (4) and second (17) holes borne by the catch (9).
4. Clasp according to claim 1, characterized by the fact that the first (1) and second (6) elements are attached respectively to first (20) and second (21) arms the free ends of which are coupled together by means of a hinge (22), one of said arms being shaped in a manner such that its length may be varied according to whether the hook borne by the first element is introduced into the first or the second hole borne by the catch.
5. Clasp according to claim 4, characterized by the fact that the second arm (21) includes a first blade (23) one end of which bears said hinge (22) and a second blade (24) provided with opposed slideways (25) with which said first blade engages, said second blade being attached to said second element, said first and second blades being provided with an arrangement (26, 27) limiting the travel of said blades relative to one another.

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