HK1198881B - Adjustable bracelet clasp - Google Patents

Description

Adjustable bracelet clasp

Technical Field

The invention relates to a bracelet clasp of the type having an unfolding buckle, comprising a first strip and a second strip hinged to each other via respective first ends between a closed position for wearing and at least one open position, the first strip carrying a fastener of a first bracelet strand, the second strip at the bottom comprising at its second end a ring defining a passage for a second bracelet strand and carrying a projecting rod intended to be inserted in a suitable hole of the second bracelet strand to define an anchoring point for the second bracelet strand to the clasp, the clasp further comprising at least one locking member for retaining the first and second strips in their closed position.

The invention also relates to a watch provided with a clasp of this type.

Background

The necessity to provide adjustment means for adjusting the usable length of the chain is a well known matter.

On the one hand, in the case of a chain formed of links, the circumference of the user's wrist may have a value between two configurations of the chain, which differ from each other by one link. It is therefore useful to provide an adjustment device that allows finer adjustments to be made to the chain length than removing or adding links to adjust the usable length of the chain.

On the other hand, it is also known that the value of the circumference of the wrist varies with the seasons, generally reaching a maximum in summer and a minimum in winter. It is therefore also preferred to provide a fine adjustment means for adjusting the usable length of the chain, so that the wearer of the chain can adjust the chain length to improve wearing comfort.

By way of example, EP patent application No 09131060 a1 discloses a clasp with an unfolding buckle comprising a cover with a series of pairs of holes for receiving the ends of bars connecting the bracelet. To solve the above problem, two pairs of adjacent holes are spaced apart by a distance to define an adjustment pitch of the usable length of the chain.

However, this type of device for adjusting the chain length is not aesthetically pleasing, since the adjustment holes are visible at the side of the cover. In addition, the adjustment of this type of clasp requires a certain dexterity, since a pointed tool must be inserted into the hole to press the bar securing the bracelet, which may lead to the cover being damaged if the person performing the adjustment is awkward.

To avoid this, alternative means are disclosed in, for example, EP patent No 0350785B 1 which discloses a clasp similar to the above, but which instead includes means by which the usable length of the bracelet can be adjusted without tools. In fact, the clasp disclosed in this patent is of the type with an unfolding buckle comprising two strips hinged to each other by means of a pin passing through both of them, wherein each strip carries at its end a fastener of the bracelet. The first strip carries a hook for engagement in a hole arranged on the second strip, in order to cooperate there with a spring pin for locking the hook and thus the clasp in the closed condition. The second bar comprises two portions slidable with respect to each other within a predetermined range, which define an adjustment pitch of the usable length of the adjustment chain. The first of the two parts carries the hinge connecting it to the first strip, while the second part carries the locking spring pin. The hole in which the hook engages to lock the clasp has a length in the longitudinal direction of the bracelet that corresponds to the sliding range of the two parts of the second strip. The spring pin has a central portion defining two positions for the hook portion in the longitudinal direction of the chain, which provide two different chain usable lengths. The control member, which in particular comprises a pusher, can actuate the spring pin to release the hook and open the clasp.

It should be noted that one disadvantage of this structure is that: the length adjustment of the bracelet cannot be performed each time the clasp is opened. Thus, each time the clasp is closed, the wearer of the bracelet must check that the hook portion is inserted on the side of the middle part of the spring pin matching the desired bracelet length.

As an alternative to avoiding such drawbacks, adjustment devices comprising specific locking members have also been proposed.

EP patent application No 1378185 a1 provides one such example.

However, these devices generally have a complex and conspicuous design, since they may comprise at least one control for locking the clasp, at least one additional control for locking the adjustment device and usually at least one elastic return.

Disclosure of Invention

The main purposes of the invention are: the drawbacks of the known prior art clasps are overcome by proposing a clasp for a bracelet comprising an adjustment device for adjusting the usable length of the bracelet, which has a simple structure, preferably providing a stable adjustment, including that it is also easy to operate when the clasp is open.

The invention therefore relates more particularly to a chain clasp of the above-mentioned type, characterized in that the loop (loop) has a plurality of positions substantially aligned in the longitudinal direction of the chain, each of said positions being able to cooperate with a lug (lug) to ensure the assembly of said lug onto said loop and to define a predetermined position of the anchoring point associated with a predetermined usable length of the chain.

Thanks to these features, the adjustment device of the invention has a very simple design combined with a delicate structure, since it is hidden under the chain when it is worn.

In general, each of said positions may advantageously be defined by a hole arranged in said ring and in which said lug may be partially engaged.

Thus, a lug in the shape of a screw foot (screw foot) may be provided for each position to be screwed into one or the other position or alternatively defined by a hole just through the ring, the lug being arranged to cooperate with a screw passing through either position.

These methods of assembling the nosebars onto the rings make it possible to easily adjust the chain length simply by unscrewing the nosebars before screwing them into different positions.

In addition, the present invention solves additional technical problems in preferred variant embodiments, combining the above features.

Indeed, clasps with unfolding buckles are known in which a second strip carries two lugs, the second lug holding the respective bracelet strand against the strip at a distance from the first lug and thus improving the overall holding effect of the bracelet strand to the clasp.

FR patent application No 2716778 a1 discloses a clasp of this type, which, however, has drawbacks due to the fact that the distance between the two projecting bars is defined by design. Of course, commercially available chains do not all have the same pitch between their holes. Thus, when the user wants to replace the bracelet, he must be assured of using a new bracelet having an integer number of hole pitches matching the distance between the two projecting bars, otherwise it is not possible to assemble the bracelet to the clasp.

The clasp according to the invention as described above may comprise an additional lug substantially aligned in the longitudinal direction of the bracelet with the lug carried by the ring.

The possibility of varying the position of the first projecting bar therefore means that the distance between the first projecting bar and the additional projecting bar can be varied, which allows it to be adapted to chains with different pitches. Thus, the clasp advantageously allows the use of a greater number of commercially available bracelets than the prior art clasps previously described.

In addition, in general, the first strip may be arranged to carry an adjustment device for adjusting the usable length of the chain, the adjustment device being arranged to adjust the position of the fastener relative to the loop.

In this case, the adjustment device may comprise a frame carrying the fastener and being movable between a plurality of positions in the longitudinal direction of the chain.

Drawings

Further characteristics and advantages of the invention will emerge more clearly from a reading of the following detailed description of a preferred embodiment, given by way of non-limiting example with reference to the accompanying drawings, in which:

FIG. 1 illustrates a simplified overall perspective view of a snap hook according to a preferred embodiment of the present invention, with the hook in a closed state and shown from a first side.

FIG. 2 is a perspective view of the clasp of FIG. 1 shown from a second side.

FIG. 3 is an exploded perspective view of the clasp of FIG. 1.

FIG. 4 is a longitudinal cross-sectional view of the clasp of FIG. 1.

FIG. 5 is a cross-sectional view of a design detail of the clasp of FIG. 1.

Detailed Description

The clasp shown in the figures in a non-limiting manner is a preferred embodiment of the invention. More specifically, clasp 1 is of the type with an unfolding buckle and is used for a watch bracelet or bracelet.

As shown more particularly in fig. 1 to 3, the clasp 1 comprises a first strip 2, which first strip 2 is hinged, in a non-limitative way, on a second strip 4 by a pin 6 associated with a sleeve 7. Each strip has an elongated shape in the longitudinal direction of the chain and is slightly curved to fit the shape of the wearer's wrist.

The first bar 2 comprises two columns 8, the two columns 8 being arranged in contact with each other at their respective ends on the side of the pin 6, each column having a cut-out so that the columns do not contact each other over most of their length.

Each post 8 carries, near its end furthest from the pin 6, an extension 10 which extends in a direction perpendicular to the longitudinal direction of the bracelet to form a pusher defining a control for opening the clasp, as shown in fig. 3.

Furthermore, the free end of the first bar 2 carries an adjustment device 12, which adjustment device 12 is used to adjust the usable length of the bracelet associated with the clasp 1.

The adjustment device 12 includes a cover 14, the cover 14 having an upper wall 16, the upper wall 16 carrying a side wall 18. The side wall 18 is provided with two holes for receiving one end of a chain-securing rod 20 in a conventional manner.

The second bar 4 comprises two arms 22, the two arms 22 being connected together by a crosspiece 24 located in the central region of the second bar 4. The arm 22 extends through a curved portion 26, the curved portion 26 carrying a loop 28 of the chain, the loop 28 being offset with respect to the general direction of the arm 22 to define a recess for the chain.

The ring 28 has a plurality of holes 30, said holes 30 being evenly spaced from each other and allowing the insertion of male stems 32 for engagement in the holes of the bracelet, to define anchoring points for the bracelet to the clasp 1. Thus, the holes 30 define potential locations for locating the lugs 32 on the loop 28 to change the location of the anchorage points of the bracelet on the clasp and thus the length of the bracelet when worn, when the clasp has a single lug for securing the bracelet.

The lug 32 takes the form of a screw foot and is associated with a screw 33, the screw 33 being arranged through the hole 30 in order to assemble the lug to the ring 28. Advantageously, the lug is partially engaged in the hole 30 by a non-circular portion of the outer periphery, which makes it easier to screw in and screw out the lug.

Of course, it is contemplated that other similar structures may be used to assemble the lug to the ring without departing from the scope of this invention. For example, each hole may be tapped, and the lug may include suitable threads to allow it to be screwed directly into the hole.

Each curved portion 26 has a small tongue 34 for improving the holding effect of the bracelet strand when positioned on the clasp 1. The cross-post 24 carries an additional, optional lug 36, which lug 36 is intended to engage in another hole in the bracelet to further enhance the retaining effect of the bracelet on the clasp.

The nose bar 32 can be placed in one hole 30 or another to define a distance between the nose bar and the additional nose bar 36 that matches an integer multiple of the pitch of the holes arranged on the chain.

In fact, commercially available chains do not necessarily all have the same pitch between their holes. Thus, when a user wishes to replace a chain, if the pitch of the new chain differs from the pitch of the old chain, the user can alter the position of the nose bar 32 on the loop 28 to match the distance between the nose bars 32 and 36 to the multiple pitches of the new chain so that each nose bar can engage in one of the chain holes.

It will be noted that this simple operation requires only the use of a screwdriver to unscrew and then screw into the nose bar 32.

The space between the arms 22 of the second strip 4 defines, in a known manner, a recess for housing the first strip 2 in the closed condition of the clasp 1.

Conventional locking means are provided to hold the clasp in the closed condition. The outer edge of the column 8 has a thickening 38 close to the pusher 10, said thickening 38 being intended to cooperate by friction with the inner edge of the second bar 4 at the recess. In particular, each inner edge of the second bar has a hollow (hold) 40, in which hollow 40 the respective thickened portion of the first bar 2 engages when the clasp is closed. The cut-out formed on each post 8 frees up a space that allows the post to deform elastically when locking the clasp or when the pusher 10 is actuated to release the thickened portion 38 from the hollow 40, thereby opening the clasp.

EP patent application No 09131060 a1 discloses in detail a clasp of this type, to which the person skilled in the art can refer if necessary.

Each pusher 10 extends through a latch 42 of an adjustment device for adjusting the usable length of the chain.

Each latch 42 comprises a plate 44 with a slot 46, the slot 46 being oriented in the longitudinal direction of the chain and having two notches 48 at its ends.

The latch is shaped to define a recess 50 therebetween for receiving an intermediate member 52. A projection 53 is provided on the latch 42 to hold the intermediate member.

The first function of the intermediate member 52 is to provide a bearing surface for a first end of the spring 54, the second end of the spring 54 resting on the corresponding plate 44, these springs being arranged to keep the latch 42 in the closed state.

The second function of the intermediate member is to act as a spacer to improve the structural stability of the adjustment device.

In fact, as is clear from fig. 3, the frame of the adjustment device comprises a lower wall 56, the lower wall 56 being fixed to the upper wall 16 of the cover 14 by means of two screws 58. Also, the upper wall 16 and the intermediate member 52 have respective bearing surfaces against which the lower wall 56 is disposed, thereby improving the stability of the respective assembly.

A screw 58 is disposed through the slot 46. The latch 42 is thus disposed between the lower wall 56 and the upper wall 16, being held there by the cooperation of the slot 46 and the screw 58.

In addition, the intermediate member 52 carries a ball key 64 for identifying (index) various possible adjustment configurations.

The operation of the adjustment device 12 will now be explained with reference to fig. 5.

Fig. 4 shows a longitudinal section through the clasp 1.

The assembly of the lug 32 to the ring 28 and the various positions that the lug 32 can occupy in the longitudinal direction of the bracelet with respect to the different positions 30 are clearly shown in fig. 4 to define the different anchoring points of the respective bracelet on the clasp 1.

In the embodiment shown, clasp 1 comprises an additional lug 36, this additional lug 36 being intended to cooperate with another hole in the same bracelet associated with lug 32; the lug 32 is movable between three possible positions defined by the three positions 30 of the ring 28 to vary the value of the distance between the two lugs 32 and 36 according to the pitch of the holes of the bracelet associated with the clasp.

The adjustment means 12 allow the available length of the chain to be adjusted.

Fig. 4 also better illustrates how the ball key 64 cooperates with the upper wall 16 of the cover 14 to identify the various possible adjustment positions of the clasp 1. A hollow 66 is disposed within the upper wall 16 to cooperate with the ball key 64 and identify various locations.

The clasp 1 is shown in its long configuration in fig. 4. If the cover 14 is moved to the left in the figure, the chain (not shown) is shortened.

Fig. 5 shows a cross-sectional view of the adjustment device 12 in a mid-plane and helps to understand how the adjustment device operates.

The intermediate member 52 has a small tongue 68, the tongue 68 defining two bearing surfaces for a first end of the spring 54, which acts on the latch 42 to keep it in the closed state.

When the pusher 10 is released, the rest shape of the column 8, assisted by the action of the spring 54, keeps each latch 42 in a distal position (remote position) corresponding to the closed state.

In this configuration, each screw 58 is located in one of the notches 48 and the frame cannot move relative to the latch 42 in the longitudinal direction of the chain.

When the pusher 10 is actuated, the latches 42 move toward each other to become open.

The notches 48 move during this operation, the screw 58 thus lying on the axis of the slot 46 and thus being able to slide along the slot to position itself opposite one notch 48 or the other as required. Thus, when the user actuates pusher 10 to place latch 42 in the open state, the user can then operate lid 14 and move lid 14 in the longitudinal direction of the chain to change the available length of the chain. When the screw 58 is once again opposite one of the notches 48, the column 8 returns to the rest shape by the elastic and synchronous action of the spring 54, if the pusher 10 is not operated by the user. This action returns the latch 42 to the closed condition and thus locks the adjustment member including the cover 16 associated with the lower wall 56 and the screw 58.

From this description it is clear that the clasp of the invention comprises a projecting bar that can be moved to adjust the usable length of the bracelet when the clasp has only one projecting bar or to adjust the distance between two projecting bars when the clasp has two projecting bars. The projecting lever is simple in design and operation and enables the user to easily adjust the clasp when desired.

The above description is intended to describe specific embodiments by way of non-limiting example, and the invention is not limited to the implementation of some of the specific features just described, such as the shapes specifically shown and described or the way they cooperate in locking a clasp.

Those skilled in the art will not encounter any particular difficulty in modifying the content of the invention to suit their personal needs and in implementing a clasp, in particular for a timepiece, without departing from the scope of the invention. It is noted that, for example, those skilled in the art will not encounter any particular difficulty in adapting the teachings herein to the design of a deployment buckle having a different configuration than that shown and described.

Furthermore, the clasp according to the invention is not limited to the use of three positions 30 for the projecting bar or even two positions for adjusting the usable length of the bracelet by means of the adjusting device 12. Indeed, those skilled in the art will not encounter any particular difficulty in adapting the teachings herein to implement clasps having a greater number of possible adjustment positions.

Similarly, it is possible to provide a plurality of possible positions substantially aligned in the longitudinal direction of the bracelet for assembling the second lug 36 to the crosspiece 24, thus providing, by the movement of the two lugs, an adjustment device for adjusting the usable length of the bracelet, while maintaining the possibility of adjusting the distance between said lugs according to the pitch of the bracelet to be assembled to the clasp, without departing from the scope of the invention.

Claims (8)

1. Bracelet clasp (1) of the type with an unfolding buckle, comprising a first strip (2) and a second strip (4), hinged to each other via respective first ends between a closed position for wearing and at least one open position, the first strip (2) carrying a fastener (20) of a first bracelet strand, the second strip (4) at the bottom comprising at its second end a ring (28), the ring (28) defining a passage for a second bracelet strand and carrying a projecting rod (32) intended to be inserted in a suitable hole of the second bracelet strand to define an anchoring point for anchoring the second bracelet strand to the bracelet clasp (1), the bracelet clasp (1) further comprising at least one locking member (38) for holding the first strip (2) and the second strip (4) in their closed position, 40) characterised in that said loop (28) has a plurality of positions (30) substantially aligned along the longitudinal direction of the chain, each of said positions (30) being able to cooperate with said nose bar (32) to ensure the assembly of said nose bar (32) onto said loop (28) and to define a predetermined position of the anchoring point associated with a predetermined usable length of said chain.

2. The bracelet clasp (1) according to claim 1, characterized in that each of the positions (30) is defined by a hole arranged in the ring (28) and in which the projecting bar (32) is partially engageable.

3. The clasp (1) according to claim 2, wherein the male stem (32) can be screwed into one or other of the positions (30).

4. A clasp (1) according to claim 2, wherein each of said positions (30) is defined by a hole passing right through the ring (28), the male stem (32) taking the form of a screw foot arranged to cooperate with a screw (33) passing through either of said positions (30).

5. The clasp according to claim 1, wherein the second strip (4) comprises an additional lug (36), the additional lug (36) being substantially aligned in the longitudinal direction of the chain with the lug (32) carried by the ring (28).

6. The bracelet clasp (1) according to claim 1, characterized in that the first strip (2) carries an adjustment device (12) for adjusting the usable length of the bracelet, the adjustment device (12) being arranged to adjust the position of the fastener (20) with respect to the projecting bar (32) carried by the ring (28).

7. The bracelet clasp (1) according to claim 6, characterized in that the adjustment device (12) comprises a frame (14, 15, 56) carrying the fastener (20) and movable between a plurality of positions in the longitudinal direction of the bracelet.

8. Watch comprising a bracelet provided with a bracelet clasp (1) of the type with an unfolding buckle, comprising a first strip (2) and a second strip (4), hinged to each other via respective first ends between a closed position for wearing and at least one open position, the first strip (2) carrying a fastener (20) of a first bracelet strand, the second strip (4) at the bottom comprising at its second end a ring (28), the ring (28) defining a passage for a second bracelet strand and carrying a lug (32) intended to be inserted in a suitable hole of the second bracelet strand to define an anchoring point for anchoring the second bracelet strand to the bracelet clasp (1), the bracelet clasp (1) further comprising means for retaining the first strip (2) and the second strip (4) in their closed positions -at least one locking member (38, 40), characterized in that said loop (28) has a plurality of positions (30) substantially aligned along the longitudinal direction of the chain, each of said positions (30) being able to cooperate with said lug (32) to ensure the assembly of said lug (32) onto said loop (28) and to define a predetermined position of the anchoring point associated with a predetermined usable length of said chain.