WRISTBAND CLOSURE THAT INCLUDES AN ADJUSTING DEVICE FOR THE LENGTH OF THE WRISTBAND

Description

technical field

[0001] The present invention relates to the field of bracelets, particularly for watches. It concerns a clasp for bracelets that allows the bracelet length to be adjusted. The invention also relates to a length adjustment device and a wristwatch comprising the clasp and / or the length adjustment device. State of the art and problems that led to the invention

[0002] A clasp for wristwatches typically consists of two fasteners for attaching the free ends of the strap, and a locking or latching mechanism to secure the two fasteners, and thus the free ends of the strap, in a stable closed or locked position. This position is also the working position, as it allows the wristwatch to be worn on the wrist. There are many types of clasps, such as the tang buckle or the folding clasp, which is aesthetically pleasing.

[0003] Watch clasps or bracelets generally include a means of adjusting the bracelet length. Typically, in the case of leather or plastic bracelets, the free end of one of the two strap strands has a series of holes distributed lengthwise along the bracelet. The free end of the other strap strand has a connecting device, such as a pin buckle, allowing the two strands to be joined by inserting the pin into the hole corresponding to the desired length. In the case of metal link bracelets, the bracelet length is adjusted by removing or adding a link to one or both strands of the bracelet.

[0004] The prior art includes clasps for wristwatches that allow for fine adjustment of the strap length. Such fine adjustment is desirable for precisely adapting the strap length to the wearer's wrist. Furthermore, as noted in document CH 704 335, a wearer's wrist size can vary with changes in temperature, for example. Therefore, the same wearer may regularly wish to fine-tune the strap length for optimal comfort.

[0005] The fine length adjustment mechanism is generally designed to allow the bracelet length to be adjusted up to a maximum distance defined by the coarse length adjustment mechanism. Depending on the clasp type, this distance may correspond to the size of the links or to the distance between the holes in the bracelet band. The fine adjustment mechanism is preferably arranged to allow length adjustment with a precision defined by the discrete distances of the fine adjustment notches along the entire adjustable length of the bracelet. In practice, fine adjustment can often be made over a total distance of 3 to 10 mm, at intervals of 1 to 2.5 mm, for example.

[0006] The fine adjustment mechanism of a bracelet clasp typically consists of a movable part mounted on one section of the clasp and carrying one of two fastening elements, with the other fastening element attached to another section of the clasp. Fine adjustment is achieved by moving the movable part relative to the clasp assembly and locking it in the position corresponding to the desired bracelet length. Often, the fine adjustment mechanism incorporates notches or teeth that define discrete length positions for fine adjustment. The notches may also be part of the mechanism that locks the movable part in a specific length position.

[0007] Document CH 704 335 discloses a folding clasp in which a fastening member is attached to a carriage arranged to slide in a housing on a clasp blade. The clasp has a pull tab arranged to cooperate with the carriage and capable of occupying two axial positions so that the carriage is locked and unlocked when the pull tab is in either of the two axial positions. A drawback of this mechanism is that at least one of the two opposing push tabs of the pull tab protrudes from the lateral walls of the clasp blade. The protruding push tab is liable to snag on an external object, for example, clothing.

[0008] As mentioned in documents CH 704 335, EP2452583 and CH700230, it may be desirable for the bracelet length to be adjustable independently of the clasp's state – closed or open. A clasp according to the preamble of claim 1 is described in document EP0819391.

[0009] Another objective is to provide a clasp whose length adjustment device is completely separate and independent from the clasp's closing mechanism, or a length adjustment device that can be associated with any type of clasp, whether it be a folding clasp, a pin buckle clasp, or another type of bracelet clasp.

[0010] An objective of the invention is also to implement a clasp with an aesthetically pleasing overall appearance. In this regard, a clasp whose adjustment mechanism remains discreet and is integrated into the overall shape of the clasp may be desirable. For example, it is an objective to avoid the presence of externally visible notches or longitudinal openings along a side wall of a folding clasp's shackle. Summary of the Invention

[0011] The present invention relates to a clasp for bracelets of the type comprising first and second free ends, the clasp having first and second bracelet fastening members intended to be made respectively fixed to said first and second free ends of the bracelet, said fastening members being movable relative to each other between at least one open position and a closed, service position, in which they are closer to each other than in the open position; the clasp comprising: locking means for opening and closing the clasp; a first support carrying a bracelet length adjustment device, said adjustment device having a movable part to which one of the two fixing members is attached, said movable part being pivotally mounted on said first support, an axis of a locking element constituting the pivot axis of said movable part, characterized in that the locking element is intended to be moved axially to unlock the adjustment device and to allow adjustment of the bracelet length.

[0012] Preferred embodiments are defined in dependent claims.

[0013] According to Article 69 of the European Patent Convention (EPC), the scope of protection conferred by the European patent or by the European patent application is determined by the claims. However, the description and drawings serve to interpret the claims. Brief description of the drawings

[0014] The features and advantages of the invention will become clearer upon reading a description of two preferred embodiments, given solely by way of example and in no way limiting, with reference to the schematic figures in which: There figure 1 is a perspective view of a bracelet clasp according to an embodiment of the present invention. The clasp is shown in the closed position. figure 2 is a perspective view of the clasp of the figure 1 shown in the open position. figure 3 is a top view of the clasp of the figure 1 . There figure 4is a longitudinal sectional side view of the clasp of the figures 1 to 3 shown in the closed position. figure 5 is a perspective view of the blade including the clasp length adjustment device figures 1 to 4 The bracelet length adjustment mechanism is shown in an exploded view. figure 6 is a perspective view of the blade including the clasp length adjustment device figures 1 to 4 . THE figures 7A to 7E are perspective views (A, B, D, E) and a lateral elevation view (C) of the moving part of the clasp of the figures 1 to 4 . THE Figures 8A And 8 B are cross-sectional views showing the clasp length adjustment device figures 1 to 4 respectively in rest position and in activated position. Figures 9A And 9 B are longitudinal sectional top views showing the clasp length adjustment device figures 1 to 4respectively in rest position and in activated position. Figure 10 is a perspective view of a bracelet clasp which, as a whole, is not covered by the claims. The clasp is shown in the closed position. figure 11 is a perspective view of the clasp of the Figure 10 shown in the open position. figure 12 is a top view of the clasp of the Figure 10 . There figure 13 is a longitudinal sectional side view of the clasp of the Figures 10 to 12 shown in the closed position. figure 14 is a perspective view of the blade including the clasp length adjustment device figures 10 to 13 The bracelet length adjustment mechanism is shown in an exploded view. figure 15 is a perspective view of the blade including the clasp length adjustment device figures 10 to 13 . THE Figures 16 A And 16 B are perspective views of the moving part of the clasp of the figures 10 to 13 . There figure 16 Cis a top view of the moving part of the clasp shown figures 10 to 13 The positions of the recesses and holes arranged in this part are indicated by dotted lines. Figures 17A and 17B are cross-sectional views showing the clasp length adjustment device figures 10 to 13 respectively in rest position and in activated position. Figures 18A and 18B are longitudinal sectional top views showing the clasp length adjustment device figures 10 to 13 respectively in rest position and in activated position. Methods of embodiment and description of the figures

[0015] The present invention relates to a clasp, in particular a clasp for a bracelet. According to a preferred embodiment, the invention relates to a clasp for a watch bracelet, preferably for a wristwatch. The bracelet can be of any type, such as, for example, made of flexible plastic, leather, or comprising an assembly of links, for example, made of metal.

[0016] Generally, the bracelet consists of two longitudinal sections, designated as the first and second strands (not shown). Each strand is designed so that one end is attached to the watch case, while the other is designed to be fastened to a clasp attachment point. As shown below, in the case of a pin buckle, the end of one of the strands has a series of holes, and the approximate length is adjusted by selecting the hole into which the pin is inserted.

[0017] To describe the invention with reference to the figures, the expressions "strap length direction" or "strap longitudinal direction" are used to designate an axis that is the axis of the two strap strands, assuming the strap is laid flat and detached from a watch. When the strap is closed, the "strap length direction" refers to the line that follows the circumference of the strap. The strap length, adjusted by fine-tuning using the clasp adjustment device according to the invention, lies in the strap length direction. In the case of a wristwatch with a conventional dial, an axis connecting the numerals 6 and 12 on the dial generally follows the strap length direction as defined herein.

[0018] If the locking mechanism of the length adjustment device is disregarded, the clasp shown in the figures is substantially symmetrical and therefore contains a plane that constitutes a plane of symmetry in embodiments where the clasp is perfectly symmetrical. In this description, this plane, which extends along the length of the bracelet and the clasp, is considered the "plane of symmetry," even if the clasp is not perfectly symmetrical, for example, due to the positioning of the length adjustment device and its locking mechanism.

[0019] The term "orthogonal" refers to an axis that is perpendicular to the "direction of the bracelet's length" and perpendicular to the clasp's plane of symmetry. In the case of a dialed wristwatch, an axis connecting the numerals 3 and 9 on the dial has an "orthogonal" direction according to this definition.

[0020] A "radial" axis is an axis that is radial to the axis of the wrist or forearm of a wristwatch wearer. The radial axis extends in the plane of symmetry or in a plane parallel to the plane of symmetry. In the view of the figure 4 , the "radial" axis is an axis that is essentially "vertical", and the two terms are used interchangeably in this description.

[0021] The terms "bottom" and "top" generally refer respectively to the bottom and top of the clasp as shown in the figure 4 The expressions "below" and "above" are to be understood in a similar way, with structural elements close to the wrist being below higher elements.

[0022] While the expressions "longitudinal direction of the bracelet", "orthogonal" and "radial" refer to the orientation of an element of the clasp or an axis of that element, these expressions concern the orientation of the element or its axis when the clasp is closed.

[0023] According to one embodiment, the clasp of the invention is a folding clasp, a folding buckle, or a folding buckle. This type of clasp is known, for example, from patent documents EP 0913106, CH700230, EP2452583, EP2361523, and CH704335. The clasp comprises at least two longitudinal clasp segments. In this description, these longitudinal segments are also referred to as the "blades" of the clasp. Generally, a clasp comprises two or three longitudinal segments. The clasps shown in the figures are three-blade clasps 20, 22, 23. Of course, it would be entirely possible to make the clasp of the invention with a two-blade folding buckle or even with a buckle of the type with a single prong. It should be noted that the clasps shown in the figures combine the features of a folding clasp with a bracelet strand attachment known from the pin buckle.The present invention also considers clasps of the pin buckle type only. A pin buckle type clasp without a folding clasp represents one embodiment of the invention.

[0024] Indeed, a person skilled in the art will understand that the bracelet length fine adjustment device according to the invention can be adapted to any type of clasp and is not limited to a particular type of clasp.

[0025] Locking means for folding clasps are known in themselves. The locking mechanism 3 used in the clasps shown in the figures will be briefly described since it is not the core of the invention. In the clasps shown, the three-bladed clasp 10, 110 comprises a central blade or first blade 20 which includes two lateral uprights 21.1, 21.2, separated from each other by a transverse spacer 41 disposed at a position between the two ends 24a, 24b of the central blade 20.

[0026] The central blade 20 is elongated along the longitudinal direction of the bracelet and slightly curved to better fit the shape of the wearer's wrist. The central blade 20 comprises a lower surface, intended to be in contact with the wearer's wrist, and an upper surface 19a, visible on the figures 1-3The upper surface can be seen from the outside when a wearer wears a wristwatch with the clasp. As will be described below, in a closed clasp position, the clasp's blades form a common upper surface, largely following the upper surface of the central blade 20.

[0027] A lateral blade 22, 122, hereinafter also called the second blade 22, 122 or inner blade, serves as a support for the fine length adjustment device 5, 105. Hereinafter, this device will generally be called the "length adjustment device" or simply the "adjustment device". The second blade 22, 122 has opposing first and second ends 25a, 25b. At its first end 25a, the second blade 22, 122 is pivotally articulated with the first end 24a of the central blade 20. The second end 25b of the second blade 22, 122 of the clasp shown in the figures is free in the sense that it is not articulated with any other blade of the clasp.

[0028] Another lateral blade 23, hereinafter also called the third blade, also has first and second opposing ends 26a, 26b. The first end 26a of the third blade is pivotally mounted to the second end 24b of the central blade 20.

[0029] The two lateral blades 22, 122 and 23 are thus articulated towards the ends of the central blade 20 and between the lateral uprights 21.1, 21.2, so as to be able to fit exactly into the space 40 provided between them by the transverse spacer 41, to define a closed clasp position, shown in Figures 1 , 3 , 4 , 10 , 12 And 13 . The second blade 22, 122 also includes, on its lower face, a niche 27 which will be occupied by the transverse spacer 41 when the second blade is lowered into its position between the two lateral uprights 21.1, 21.2.

[0030] It will be understood that in the closed position, the lateral sides 158, 159 ( Figures 5 , 9 , 8B , 15 And 17B ) of the second blade 22, 122 are aligned with and / or extend alongside the inner lateral surfaces of the two lateral uprights 21.1, 21.2 of the first blade 20.

[0031] The clasp of the invention preferably includes locking means for keeping the clasp stably in the closed position and for allowing the clasp to be opened. The present invention is not limited to a particular locking mechanism or device. The mechanical principle of the locking device shown in the drawings, designated as a whole by reference number 3 ( figure 1The mechanism of the third blade 23 is known in itself and will only be described briefly below. It will be noted that the third blade 23 consists of two half-blades 23.1, 23.2 separated by a slot, the latter allowing the two half-blades to move closer together along an orthogonal direction, perpendicular to the longitudinal direction of the clasp. The half-blades are, however, held apart by a spring housed in hollow cylinders surrounding the axle 3.4 of the pin buckle 2, which itself serves as a fastening element for one free end of a bracelet strap. The axle 3.4 is housed in two coaxial tubes 3.5 having orthogonal axes, which are positioned at the free ends of the half-blades 23.1, 23.2. The axle connects the two ends of the frame 2.1 of the pin buckle so as to provide a hinge for the latter. Pushbuttons 3.2 are provided on either side of the ends of the frame 2.1 of the pin buckle, as a lateral extension of the axle 3.4. They are held on an orthogonal axis, separated from each other by the aforementioned springs.

[0032] A wearer wishing to open the clasp 10 can press the pushers 3.2 by holding them between their thumb and forefinger. The pressure on the pushers 3.2 is transmitted to the half-blades 23.1, 23.2, whose free ends will move closer together. This movement results in the release of the raised sections or hooks 3.1 ( Fig. 2 ), arranged laterally on the half-blades 23.1, 23.2 of their respective seats 3.3 arranged in the inner lateral surfaces of each of the uprights 21.1 and 21.2 of the main blade 20.

[0033] To close the clasp, the wearer first ensures that the second blade 22 is in the folded position, in the space 40 provided between the side uprights 21.1 and 21.2. The second blade contains ball ratchets 3.5 ( Fig. 5) which cooperate with recesses formed in the inner side faces of each of the uprights 21.1 and 21.2, to prevent the second slat 22 from pivoting out of the lowered position when the user wishes to close the clasp by holding the third slat 23. The user returns the third slat to the closed clasp position, for example, by pressing on the third slat until the hooks 3.1 are in their respective seats 3.3. To do this, and depending on the shape of the hooks and their seats, it may be necessary to press on the pair of side pushers 3.2 as in the case of opening the clasp. Alternatively, the user pressing on the third slat in a radial direction perpendicular to the general plane of the clasp is sufficient to bring the half-slats 23.1, 23.2 together, which is necessary to fold the third slat until it is in the locked position.In the latter case, the closure can be achieved by snapping. It can also be mentioned that, in the closed clasp position, the free end 26b of the third blade 23 rests against the free end 25b of the second blade 22, so as to lock it in the folded and closed position.

[0034] In one embodiment, when the clasp is in a closed position, the upper surfaces of the first and second blades 20, 22 form a common upper surface 19a, 19b. The first and second blades 20, 22 are arranged such that at least a portion of their respective upper surfaces 19a, 19b form a common and / or homogeneous surface when the clasp is closed. In other words, a portion of the upper surfaces 19a and 19b lie in a single plane. This plane is preferably slightly curved, in accordance with the general construction of the clasp described above. In longitudinal section of the clasp, along the axis of symmetry, as shown in the figure 4 , the common upper surface 19a, 19b of the first and second blades 20, 22 follows a single line, indicated by a dotted line at the figure 4 .

[0035] Similarly, the first and third blades 20, 23 are arranged so that at least part of their respective upper surfaces 19a, 19c form a common and / or homogeneous surface when the clasp is in its closed position. The common surface of the first and third blades 20, 23 is also indicated by a dotted line in the figure 4 .

[0036] The aforementioned arrangement is the result of inserting the side blades 22, 23 into the space 40 arranged between the two side uprights 21.1, 21.2 of the central blade 20, making it possible to achieve an aesthetic and harmonious appearance, while saving space along the radial axis and creating a slim closure.

[0037] In one embodiment, the clasp comprises a first and a second fastening member 1, 2. The present invention is not limited to a particular fastening member, and numerous means are known for attaching the free ends of the two bracelet strands to a clasp. In the embodiment shown in the figures, the first fastening member is in the form of a crossbar 1, and the second fastening member is in the form of a pin buckle 2. As can be seen in the figures 4 And 13A tenon 2.3 is present on the underside of the crossbar of the frame 2.1 of the pin buckle. The free end of the bracelet strap can then be attached to the clasp by inserting the tenon 2.3 and / or the pin 2.2 into holes in the end of one of the two bracelet straps. The tenon 2.3 further illustrates the ornamental function of the pin buckle 2. Pin buckles are generally known as standalone clasps, whereas in the case of the clasp shown in the figures, the pin buckle is combined with a folding clasp. In the case of the clasp shown in the figures, the clasp is generally opened by the locking means 3 described above and not by detaching the bracelet strap from the tenon 2.3 and / or the pin 2.2.

[0038] In one embodiment, the present invention relates to a length adjustment device for a clasp that can be made with any type of bracelet clasp. Those skilled in the art will note, upon reading the description of the two preferred embodiments, that the length adjustment device is independent of the clasp's closing or locking means. The length adjustment device allows for length adjustment regardless of whether the clasp is open or closed. Consequently, it is possible to adjust the bracelet length even while wearing a wristwatch equipped with the clasp of the invention.

[0039] The clasp according to the invention comprises a length adjustment device 5, attached to a support. In the clasps shown in the figures, the second blade 22; 122 serves as a support for the adjustment device.

[0040] As will be explained with references to figures 2 And5 The second blade 22 comprises, near its first end 25a, a base 37 for two lateral rails 8, 9 which are substantially parallel and follow the longitudinal direction of the clasp. The rails 8, 9 are separated by a space 30, provided to house the movable part 6 and allow it to move in the longitudinal direction of the clasp during length adjustment. The movable part 6 is shown enlarged in the Figures 7A to 7C .

[0041] In the embodiment shown, the longitudinal members 8 and 9 are rigidly connected only by the base 37. Consequently, the space 30, which serves as a housing for the movable part 6, extends radially through the entire blade 22. In other words, the space 30 is a notch delimited only (ignoring the locking element 7) laterally by the longitudinal members 8 and 9, and towards the first end 25a of the blade 22 by the base 37. The notch 30 is open downwards and upwards (along the radial direction) and also towards the free end 25b of the second blade 22.

[0042] The movable part 6 is shown separately to figures 7 A-7CIt has a longitudinal shape. Its thickness along an orthogonal direction allows it to be inserted and precisely housed in the space 30 provided between the two longitudinal members 8, 9. Towards one of its ends, the movable part includes a cylindrical hole 38 in an orthogonal direction, to house a shaft serving as a fastening element 1 for attaching the free end of a first bracelet strand. The shaft comprises two parts, the first 42 having a threaded tubular portion and the second 43 having a threaded end (not shown) for connection to the threaded tube. On the threaded end side, part 43 has a reduced diameter, to allow it to pass precisely through the hole 38 and to make the shaft 1 fixed to the movable part 6 when the first part 42 is screwed into the threaded portion 42.

[0043] As can be clearly seen in the Figure 7A , the movable part 6 includes a longitudinal slot 13.

[0044] In one embodiment, the locking element is a shaft and / or a locking cylinder 7 having a narrowed section 15. The dimension of the narrowed section 15 corresponds substantially to the height of the longitudinal slot 13 arranged in the movable part 6, so that the locking element can pass through said longitudinal slot.

[0045] The locking shaft 7 can be more generally referred to as the locking member or locking element 7.

[0046] As will be understood, the longitudinal extension of this slot determines the maximum distance over which the fine-adjustment device alone can adjust the bracelet length. The view of the Figure 7BThe diagram shows a series of grooves 14a, 14b, 14c, etc., arranged on one of the two lateral faces 35, 36 of the moving part, along the longitudinal slot 13. The set of grooves 14a-14f constitutes a notched portion 14 that defines the fine adjustment positions. In the embodiment shown, the lateral face with the grooves 14 is the first face 35, and the other lateral face is the second lateral face 36 of the moving part. Since the notched portion 14 is located on only one of the two lateral faces 35, 36, the moving part 6 of the embodiment shown is asymmetrical with respect to the general plane of symmetry of the clasp.

[0047] Unexpectedly, the movable part 6 is slightly curved along its longitudinal extension, similar to the curvature of the second blade 22 and preferably following the curvature of the central blade 20. Such a curvature is unexpected because it would not be conceivable in the case of a conventional clasp with a movable part sliding on a rail. As described below, the particular way in which the movable part 6 is attached to the support 22 allows the movable part to have a curved shape.

[0048] The movable part 6 is attached to the support 22 by the member 7, which is housed in a predominantly tubular housing so as to pass through the space 30 along an orthogonal axis. The element 7, passing through the longitudinal slot 13 of the movable part 6, retains the latter and attaches it to the second blade 22.

[0049] In one embodiment, said support 22 comprises two lateral stringers 8, 9, separated by a central longitudinal opening 30, and the movable part 6 is pivotally arranged in said central opening 30.

[0050] In one embodiment, the shaft and / or locking element 7 is arranged in a direction orthogonal to the direction of the bracelet length.

[0051] In one embodiment, the locking shaft is intended to be moved axially to unlock the adjustment device 5 and to allow adjustment of the bracelet length.

[0052] In one embodiment, the housing 31, 32 of the locking element 7 is arranged such that a portion of the locking element 7 is located above the first blade 20 when the clasp is in a closed position. The housing 31, 32 of the locking element 7 protrudes from the general upper surface 19b of the second blade 22.

[0053] The housing for the shaft 7 comprises two tubes 31, 32 arranged orthogonally on either side of the space 30, on the two longitudinal members 8, 9 of the second blade 22. The two tubes 31 and 32 protrude from the upper surface of the second blade and thus from the common surface between the blades of the clasp in the closed clasp position. The tubes 31, 32 therefore appear as bulges 31, 32 on the longitudinal members 8, 9 of the second blade 22. In the embodiment shown in the figures, the tubes 31 and 32 are formed as a single piece with the second blade 22.

[0054] In one embodiment, the locking element is a locking shaft 7, housed so that its axis is located above the plane formed by the common upper surface 19a, 19b of said first and second blade 20, 22.

[0055] In one embodiment, said second blade 22 comprises first and second lateral stringers 8, 9, the movable part 6 being arranged between said lateral stringers, a first part 31 of the housing of the locking element 7 being arranged in a bulge of said first lateral stringer 8, and a second part 32 of the housing being arranged in a bulge of said second lateral stringer 8.

[0056] In one embodiment, the housing 31 of said locking element 7 extends laterally, in a direction orthogonal to the direction of the bracelet length, beyond a flank 158 of said second blade 22, to be situated above said lateral uprights 21.1; 21.2 of said first blade 20 when the clasp is in a closed position.

[0057] For example, the housing of the locking member 7 may include a tubular part 33, arranged in an orthogonal direction on said second blade 22 so as to extend beyond a lateral flank 158 of the second blade 22 and to be positioned above an upper surface 19a of the first blade when the clasp is in the closed position.

[0058] The housing for the locking shaft 7 includes tubular parts 33 and 35 ( fig. 8B ) which are part of the bulges 31, 32 on the longitudinal members 8, 9. The tubular parts 33, 35 are the parts of the housing which laterally protrude the sides 158, 159 of the second blade 22. This is notable insofar as, as described above, the second blade 22 is arranged to fit between the two uprights 21.1 and 21.2 of the first blade 20 when the clasp is in the closed position.

[0059] These lateral extensions 33 and / or 35 of the housing do not prevent this insertion because the entire housing 31, 32, and therefore also the tubes 33 and 35, are raised above the overall surface 19a, 19b, 19c of the clasp. As described herein, the first blade 20 may also include one or more notches 39.1, 39.2 to allow the second blade 22 to be lowered.

[0060] In one embodiment, one end 16 of the locking element 7 emerges through a lateral opening of the housing 31, 32, said end being arranged to form an actuation member 16 of the length adjustment device 5.

[0061] According to the invention, the movable part 6 is pivotally mounted on a first support, namely the second blade 22. The axis of the shaft 7 constitutes the axis of rotation of the movable part 6. The shaft 7 is preferably the only structural element that connects the movable part 6 to the support. Finally, the shaft 7 preferably also functions as a locking structure to secure the movable part in a position defining a fine length adjusted along the longitudinal direction of the bracelet.

[0062] In order to understand the operation of the fine length adjustment device according to this embodiment, the configuration of the locking shaft 7, its housing and the toothed portion 14 of the moving part will be described with reference to Figures 5 to 9 B .

[0063] In the embodiment shown, the locking shaft 7 is formed of two separate parts 7.1, 7.2. The first part 7.1 comprises a series of coaxial cylinders having different diameters. The cylinder 16 at one end of part 7.1 constitutes an actuating element in the form of a pusher 16. In the embodiment shown, the pusher 16 comprises a cylindrical portion located at one end of the shaft 7 and forming a first section thereof. The cylinder 18 following the pusher 16 has a slightly smaller diameter compared to the diameter of the pusher 16. This section 18 can be considered a guide cylinder 18. The smaller diameter of the guide cylinder 18 gives rise to the first annular flange 44, formed between the pusher 16 and the guide cylinder 18. This first annular flange 44 serves as a bearing surface for the spring 29, as shown in the diagrams. Figures 8A And 8BThe diameter of the cylindrical section 15 located towards the end opposite the pusher 16 of the first part 7.1 is in turn reduced compared to the diameter of the guide cylinder 18. The diameter of the section 15 is substantially identical but slightly less than the axial extension (the height) of the slot 13 made in the moving part 6. This allows the precise fitting of the moving part 6 onto the shaft 7 and in particular onto the through section 15 of the shaft 7 (figures A8 and 8B). In one embodiment, said movable part 6 has a longitudinal slot 13 through which said locking element / shaft 7 passes. At its free end, the through section 15 includes an external thread, complementary to the internal thread tapped in the second part 7.2 of the shaft 7. The part 7.2 thus functions as a nut to attach the shaft in the housing formed by the tubes 31 and 32 arranged on the blade 22.

[0064] As can be clearly seen in figures 7C and 7D , the notched part 14 arranged on the first lateral face 35 of the moving part includes a series of grooves 14a-14f.

[0065] In this description, reference number 14 indicates the serration formed by a series of grooves 14a-14f or by all the grooves 14a-14f. The number 14 can also be used to refer to any single groove among the grooves 14a-14f.

[0066] In one embodiment, the locking shaft 7 has a bulge, a rim or a locking structure 17 of complementary shape to the shape of one of the grooves of the toothed part 14 arranged in the movable part 6 along said longitudinal slot 13.

[0067] The shape of these recesses is chosen so as to allow them to accommodate a locking structure or a bulge 17 arranged on the locking shaft 7. In the embodiment shown, the locking structure 17 is in fact the part 7.2, whose diameter is greater than the diameter of the through section 15, so that a third annular rim 46 is created between the through section 15 and the cylindrical section formed by the second part 7.2, hereafter also referred to as nut part 7.2.

[0068] Those skilled in the art will understand that it would also be possible, in an alternative embodiment, to make the shaft 7 by a first part comprising sections 16 and 18 and a second part comprising sections 15 and 17. In this case, section 18 could include the tapping and the free end of section 15 passing through the thread to screw the two parts together and thus attach the moving part.

[0069] In the embodiment shown, each of the recesses 14a, 14b, 14c, etc. of the movable part 6 can be considered as formed by two half-recesses, one of which is arranged above and the other below the longitudinal opening formed by the slot 13.

[0070] In one embodiment, said movable part 6 includes a toothed part 14 formed by a series of grooves 14a-14f partially traversing the movable part, so as to create, inside the movable part 6, one or more bearing surfaces 47 against which a locking structure 17 comes to rest when the length adjustment device 5 is in the locked position.

[0071] Regarding the specific shape of the notched part 14, it is helpful to understand that each groove 14a, 14b, 14c, etc., is in fact formed by a cylindrical hole (partial, blind, and / or non-through) in an orthogonal direction in the first lateral face 35 of the moving part 6. The holes that give rise to the grooves 14 have a diameter greater than the dimension in the radial direction (height) of the slot 13. On the other hand, the holes are blind because the depth of the holes is less than the dimension in the orthogonal direction of the moving part 6, in other words, less than the width of the part 6. Thus, the holes made to create the grooves 14 form a rim 47 or a plurality of rims inside the moving part 6, in particular along the slot 13 of the moving part. In the embodiment shown, these edges function as bearing surfaces for the locking shaft 7, as will be described below.Due to the diameter of the bore of the recesses 14 relative to the height of the slot, each of the internal recesses 14b-14e has a pair of rims, i.e., an upper rim and a lower rim. The two recesses located at the two opposite ends of the slot 13 (the recesses 14a and 14f shown in the . figure 7 D) include the continuous rim 47a and 47f, respectively. This continuous rim resembles the outline of a sickle ( fig. 7C ).

[0072] As can be seen at the figure 7CEach of these pairs of edges (or bearing surfaces) 47 is essentially shaped like a segment of a circle. This particular shape results from the fact that, in the embodiment shown, the holes drilled to create the recesses 14 are close together along the longitudinal direction, so that the circles defining the diameter of a hole overlap. This overlap also reduces the discrete distances required for fine adjustment and consequently allows for even finer adjustment.

[0073] The shape of the rims 47 depends partly on the diameter of the bore of the recesses 14 relative to the height of the slot 13 and partly on the shape of the longitudinal slot 13. In an alternative embodiment, the movable part 6 includes a continuous rim 47 extending along the slot 13. A continuous rim 47 could be obtained by choosing a larger diameter for the bore of the recesses, or a smaller height of the slot 13.

[0074] The bearing surface(s) 47 are preferably located in a plane parallel to the plane of symmetry of the clasp and / or in a plane parallel to the lateral surfaces 35, 36 of the moving part, as can be clearly seen in figures 7 And 8B The bearing surface(s) 47 will serve as bearing surfaces for the locking structure 17 of the locking shaft 7.

[0075] The edges 44-46 of tree 7 are also all parallel to the plane of symmetry of the clasp (vertical in the Figures 8A And 8B ).

[0076] The operation of the length adjustment device 5 and its locking device will be described below with reference to Figures 7D to 9B The housing for the shaft 7 comprises two tubes 31, 32, arranged on either side of the space 30 formed between the longerons 8 and 9. The tube 32 of the longeron 9 (hereafter: the second tube) contains only a hollow cylinder of constant diameter. In contrast, the tube 31 of the longeron 8 (hereafter, the first tube) contains, towards its outer lateral end, a hollow cylinder of enlarged diameter, forming a housing 48 for the pusher 16 ( Fig. 8 ). The second part 49 of the hollow cylinder of the tube 31 is characterized by a diameter smaller than the diameter of the housing 48. This reduced diameter allows the passage of the guide section 18.

[0077] The spring 29 rests on the rim 51, formed between the hollow and coaxial cylinders of different diameters 48 and 49 of the first tube 31, and on the first annular rim 44 of the shaft 7, delimiting the pusher 16 from the cylinder or guide section 18 of the shaft 7. Thus, the spring 29 forces the shaft 7 towards the end of the pusher 16. The latter emerges from the tube 31 to constitute an actuation member 16 which can be activated by a carrier because it is accessible from outside the clasp.

[0078] In one embodiment, the actuating member 16 is actuated by a spring 29 in the locked position. Preferably, the spring 29 is housed in the housing of the locking shaft 7.

[0079] As can be seen in Figures 8A And 9 A, the shaft 7 is held in its housing by the nut part 7.2, whose rim 46 butts up against the rim 47 inside the grooves 14 of the moving part 6. In this position, the moving part is blocked or locked, because the nut part 7.2 is inside one of the grooves 14a-14f, and opposes a movement of the moving part along the longitudinal direction of the bracelet.

[0080] The recesses 14 do not, however, prevent rotation of the moving part 6 around the axis of the shaft 7. As mentioned above, the part 7.2, one end 17 of which functions as a locking element, is cylindrical, and the recesses 14 are adjacent cylindrical bores. The section 15 of the shaft 7 passing through the slot 13 is also cylindrical and does not impede the pivoting of the moving part 6. On the other hand, the moving part 6 cannot complete a full rotation because the fastening member 1 prevents free rotation of the moving part within the space 30. When the clasp is closed, the spacer 41 can also limit the radial angle of rotation of the moving part 6.

[0081] We distinguish between the rest position and the locking position, shown in the figures 7D , 8A And 9 A , from the activated position or unlocked position, shown to figures 7E , 8B And 9B .

[0082] To finely adjust the bracelet length using the clasp of the invention, it is first necessary to move from the locked to the unlocked position. In the locked position, the moving part is prevented from moving along the bracelet's length. It should also be noted that the locked position is preferably a stable position, as it is held in place by spring 29. According to this embodiment, to unlock the length adjustment device, the wearer must apply pressure to the pusher 16. Preferably, the pusher must be held in the depressed position to prevent the locking device from returning to the locked position before the length adjustment is complete.

[0083] To adjust the length, the wearer pushes the pusher 16 against the force of the spring 29, and the locking shaft 7 thus undergoes an axial movement defined by the housing and / or hollow cylinders 48, 49, 12 inside the tubes 31 and 32 that form the housing for the shaft 7. The axial movement of the shaft 7 causes the end 17 of the cylinder 7.2 to separate from the recess 14 in which it is housed. As a result, the movable part 6 can move in the longitudinal direction of the bracelet, moving within the space 30 arranged between the longitudinal members 8 and 9. The through section 15 remains inside the slot 13 while the movable part 6 moves. The position of the locking shaft 7 along the longitudinal direction remains constant; it is held by the tubes 31, 32, which only allow its axial movement.

[0084] When the operator releases pressure on the pusher 16, the spring 29 pushes the shaft 7, and thus the end of the cylinder 17, into a locked position. As soon as the shaft 7 is aligned (coaxial with) any groove in the toothing 14, the cylindrical part 17 automatically inserts itself into this groove to block the movement of the movable part 6 in a longitudinal direction. This insertion is automatic because the spring 29 exerts force on the shaft 7, and in particular on the end of the cylinder 17, in the direction orthogonal to the bearing surface formed by the rim(s) 47.

[0085] Another clasp 110 is shown in the figures 10-18BThis clasp 110 differs from clasp 10 primarily in its length adjustment mechanism and the corresponding configuration of the blade (or support) carrying this adjustment mechanism. The closing means for opening and closing the clasp, as well as the first and second fastening elements, are identical to those of the clasp according to the first embodiment. The clasp shown in the figures 10-18B is also a three-blade clasp and its design is virtually identical to the clasp design shown in figures 1-9B .

[0086] As in the case of the clasp according to the embodiment of the invention, the clasp shown in the figures 10-18B This could be made as a double-folding clasp or even a simple pin buckle clasp. A person skilled in the art would be able to adapt this clasp to any particular type of clasp, and would be able to implement the clasp shown in the... figures 14-18using fastening devices of a different type.

[0087] The second blade 122 clasp shown to figures 14-18 is different from the second blade 22 of the first embodiment, whereas the first and third blades 20, 23 are substantially identical in both embodiments. Note the absence of the recesses 39.1 and 39.2, present on the lateral uprights of the first blade 20 of the first embodiment. As the locking shaft 107 of the clasp 110 is housed in a higher position compared to the locking shaft 7 of the first embodiment, the lateral extension 139 ( Fig. 15 ) of the locking shaft housing does not prevent the complete insertion of the second blade 122 into the space 40 arranged between the side posts 21.1 and 21.2.

[0088] The second blade 122 serves as a support for the length adjustment device 105. The second blade 122, shown separately at the figure 15, includes, at its first end 125a, a base 137 for two lateral stringers 108, 109 which are substantially parallel and follow the longitudinal direction of the clasp. The stringers 108, 109 are separated by a space 130, provided to house the movable part 106 and allow it to move in the longitudinal direction of the clasp during length adjustment. The movable part 106 is shown enlarged in the figures 16 A à 16 C .

[0089] In the clasp 110, the longitudinal members 108 and 109 are rigidly connected only by the base 137. Consequently, the space 130, which houses the movable part 106, extends radially across the entire blade 122. In other words, the space 130 is a notch bounded only (ignoring the locking shaft 107) laterally by the longitudinal members 108 and 109 and, towards the first end of the blade 122, by the base 137. The notch 130 is open downwards and upwards (along the radial direction) and also towards the free end 125b of the second blade 122.

[0090] The second blade 122 has a housing for the movable part 106, allowing it to move along the length of the bracelet during length adjustment and / or when the movable part is unlocked. Specifically, a guide rail is formed by two channels 151.1, 151.2 formed in the inner side walls of the spars 108, 109. The movable part 106 has two lateral edges 152, 152' to allow it to slide in the rail 151.1, 151.2. Towards the second end or free end 125b of the second blade 122, the rail is open so that the movable part 106 can be inserted into its housing during the assembly of the clasp 110.

[0091] The movable part 106 is longitudinal and comprises a base forming two lateral edges 152, 152' and a superstructure or vertical wall 153 which rises relative to the base along the longitudinal extent of the movable part. Towards its first end, the superstructure 153 includes a lug 154 provided with a through hole 155 to house the shaft functioning as a fastening member 1 as described above in relation to the embodiment of the invention.

[0092] Said movable part 106 comprises a first notched part 114 having a series of grooves 114a-114f, arranged along said movable part 106 and intended to cooperate with a locking rod 117, and in that said movable part 106 comprises a second notched part 115 having a series of grooves 115a-115f, intended to cooperate with a ratchet 135 arranged so as to position the movable part 106 in a determined and / or indexed position when the adjustment device 105 is unlocked.

[0093] The movable part 106 comprises a base 152, 152', slidingly housed in said second blade 22 and a structure 153 raised above said base, said first and second notched parts 114, 115 being formed in the two opposite faces of the superstructure 153.

[0094] As can be clearly seen in figures 16 A à 16 C , the longitudinal structure 153 of the movable part 106 includes first and second lateral faces 156, 157. Each of the lateral faces includes a series of grooves 114a-114f, 115a-115f to define first and second notches 114, 115.

[0095] In this description, reference numbers 114 and 115 indicate the serration formed by a series of grooves 114a-114f and 115a-115f, or the entire set of grooves 114a-114f and 115a-115f, respectively. Numbers 114 and 115 can also be used to refer to any single groove among grooves 114a-114f and 115a-115f, respectively.

[0096] In the clasp shown, the first notch 114 has a groove coaxial with the second notch 115. In other words, the grooves on either side of the superstructure 153 are aligned. This alignment of the grooves can be advantageous in the clasp's construction, but it is not mandatory. There can also be two separate notches whose grooves are not coaxial. In this clasp, the notches do not completely penetrate the wall 153. In an alternative clasp, the wall 153 has a notch comprising a series of complete holes, passing through the entire wall 153. In this case, it is not necessary to provide two separate sets of grooves, because a single set of grooves could be used as two notches on either side of the superstructure 153.

[0097] As can be seen more clearly in figures 16C , And 18 A-B The grooves 114 are not the same shape as the grooves 115. Each of the grooves in the first notch 114 is cylindrical, while each of the grooves in the second notch 115 is spherical and / or crescent-shaped. It should be noted that the shapes of the grooves 114 and 115 shown in the figures may be advantageous, but the clasp is not limited to any particular groove shapes.

[0098] The shape, configuration, and housing of the locking shaft 107 are shown in the figures 14 , 15 , 17 A, 17 B , 18 A et 18 B The locking shaft 107 is formed by two longitudinal parts 107.1 and 107.2 ( fig. 14 ), one part of which has a thread and the other a tapped hole, allowing the two parts to be connected by screwing during the assembly of the clasp. The first part 107.1 comprises two coaxial cylindrical sections 116, 118. The cylinder 116 at one end of part 107.1 constitutes an actuating element in the form of a pusher 116. In the clasp shown, the pusher 116 comprises a cylindrical part located at one end of the shaft 107 and forming a first section thereof.

[0099] The cylinder 118 of the section following the pusher 116 has a slightly reduced diameter compared to the diameter of the pusher 116. This cylindrical section 118 can be considered a guide cylinder 118. The reduced diameter of the guide cylinder 118 gives rise to the first annular rim 144, formed between the pusher 116 and the guide cylinder 118. The annular rim 144 serves as a bearing surface for the spring 29, as shown in the diagrams. figures 17A et 17B .

[0100] The second part 107.2 also comprises two parts or first and second coaxial cylindrical sections 119, 120. The free end of the first cylinder 119 includes a thread to allow screwing into the tapped hole arranged in the first part 107.1, in particular at its end opposite the pusher 116. In the second part 107.2, the cylindrical section 120 at the end opposite the threaded part has a slightly larger diameter compared to that of the cylinder having the thread, so as to form an annular rim between the two cylindrical sections 119, 120 of the second part.

[0101] A locking piece 107.3 having a hole with a diameter corresponding to the diameter of the first section 119 is fitted onto the second piece 107.2 to be retained on the annular rim of the second piece 107.2, when the latter is screwed to the first piece 107.1. The annular rim formed between the first and second cylindrical sections 119, 120 presses in particular against the locking piece 107.3 when the second piece 107.2 is screwed into the first piece 107.1.

[0102] The locking piece 107.3 includes a locking rod or pin 117, the axis of which is parallel to the axis of the locking shaft 107. The locking piece 107.3 serves to secure the locking rod 117 to the shaft 107 and to define the rod's orientation. The locking rod 117 acts as a locking structure, locking the movable part 106 in a longitudinal position defined by the carrier. Furthermore, the locking piece 107.3 includes a plate 112 connecting the hole to the rod 117. This plate, which supports both the hole in the piece and the rod 117, allows the locking piece 107.3 to also function as a stop that retains the shaft 107 in its housing.

[0103] In the clasp shown, said locking shaft 107 is integral with a locking rod 117, the axis of which is parallel to the axis of the locking shaft 107, and arranged so as to cooperate with said moving part 106 in order to lock it and thus determine a stable adjusted (or set) bracelet length.

[0104] The housing 131, 132 for the locking shaft 107 is formed by two coaxial and orthogonal cylindrical holes, arranged on either side of the space 130 between the two side rails 108, 109. The holes are arranged in two bulges 131, 132, which protrude from the side rails 108, 109 relative to the general upper surface of the second blade 122, i.e., relative to the common surface 19a, 19b, 19c of the clasp blades when the clasp is closed. The bulge 131 on the first side rail 108 extends laterally beyond the blade 122 and / or the side rail 108, to form a housing 148 for the locking shaft pusher 116. It is the tubular part 139 of the bulge 131 which protrudes laterally from the blade 122 in an orthogonal direction.

[0105] In the clasp shown, the housing 148 for the pusher 116 is a first hollow cylinder with a lateral opening, allowing the free end of the pusher 116 to protrude so that it can be actuated from the outside by a carrier. The housing 148 extends into the interior of the bulge 131 via a second hollow cylinder 149, forming a housing for the guide section 118 of the shaft 117. The diameter of the second hollow cylinder 149 is smaller than the diameter of the first hollow cylinder 148, creating an annular rim 145 inside the housing for the shaft 107.

[0106] The annular rim 145 forms the second support for the spring 29, which acts on the shaft 107, by pressing on the annular rim 144 of the pusher 116, so that the pusher 116 is forced in an orthogonal direction outwards, outside the housing 148 arranged laterally on the second blade 122.

[0107] In one embodiment, the length adjustment device 5 includes an actuating member 16, which is actuated by a spring in the locked position. Preferably, the actuating member is integral with the locking shaft 7. In another embodiment, the actuating member is coaxial with the shaft 7. In the clasps shown, the actuating member comprises a cylinder disposed at the free end of the housing 31, 131.

[0108] The shaft 107 is held in its housing by the locking piece 107.3 which rests against the movable part 106 when the locking device is in the rest position or not activated ( figure 18 A) More precisely, the plate 112 on which the locking rod 117 is arranged comes to abut against the first lateral face 156 of the wall 153 of the moving part 106, as can be seen in figures 17 A And 18 A .

[0109] The spar 109 also has holes and recesses to complete the housing for the shaft 107 in the second leaf 122. The bulge 132 has a cylindrical hole 150, open towards the outer lateral side visible at the figure 14 The cylindrical part 120 of the second part 107.2 is housed in the hole 150. To allow movement of the locking part 107, a notch 141 is provided in the inner lateral face of the second longitudinal member 109 ( Fig. 15 ).

[0110] In the clasp shown, the locking shaft 107 is arranged to pass over the moving part 106, specifically over the structure or frame 153 incorporating the notches 114. The locking structure, i.e., the rod 117 fixed to the shaft 107, extends parallel to the shaft 107, but at a level below the locking shaft 107, in order to cooperate with the notches. This arrangement results from the absence of a longitudinal slot in the moving part, as shown in the first embodiment, which allows the shaft 7 to pass through the moving part 6 in this case.

[0111] It should also be noted that the second blade 122 contains a housing 136 for the ball ratchet 135 ( Fig. 14 ). This housing is formed by a non-through cylindrical hole 136, arranged in the inner lateral face of the first spar 108. To allow the positioning of the ratchet 135 in its housing 136 during the assembly of the clasp, a through hole 138 is drilled in the second spar 109, the through hole 138 being coaxial with the housing 136 of the ratchet, to allow the insertion of the ratchet into its housing 136 in the first spar 108 through the second spar 109.

[0112] As in the case of the first embodiment, the locking element and / or shaft 7, 107, is intended to be moved axially to unlock the adjustment device 5, 105 and allow adjustment of the bracelet length.

[0113] The operation of the length adjustment device and its locking mechanism will be described below with reference to figures 17 A - 18 B We distinguish between the rest position and the locking position, shown in the figures 18 A and 19 A, from the activated or unlocked position, shown to the figures 18 B and 19B. To finely adjust the bracelet length using the clasp, it is first necessary to move from the locked to the unlocked position. In the locked position, the moving part is prevented from moving along the bracelet's length. It should also be noted that the locked position is stable, as it is held in place by spring 29. To unlock the length adjustment mechanism, the wearer must apply pressure to the pusher 116, and preferably hold the pusher down to prevent the locking mechanism from automatically returning to the locked position before the desired length is set.

[0114] As can be seen in figures 17 B And 18 BPressing the pusher 116 by the wearer causes the locking shaft 107 to move along its axis. This movement dislodges the locking rod 117 from its housing formed by a hole in the first notch 114. Consequently, the moving part 116 is no longer locked and can be moved longitudinally, thus changing the bracelet length. However, the ball of the ratchet 135 remains in a hole in the second notch 115. To move the moving part, the wearer must apply force in the desired adjustment direction. For example, the wearer can grasp the moving part 106 by holding the bar 1 of the fastening element and push or pull the moving part, depending on the desired direction.

[0115] During the movement of the movable part 106, the ball of the pawl 135 will successively engage in one after the other of the grooves 115a-115f of the notch 115. The pawl and the second notch 115 thus function as an indexing notch that predefines the distinct longitudinal positions in which the movable part 106 can be locked. The second notch is also called the "pre-positioning notch" or "indexing notch" of the movable part 106. As mentioned with reference to the figure 16 A The first notch 114 is formed by separate, spaced holes or grooves 114a-114f. The notch formed by the pawl 135 and the grooves 115 serves to stop the moving part in positions where it can be locked by the locking shaft 107. The absence of the second notch 115 would not make fine adjustment impossible, but its presence makes length adjustment more convenient.

[0116] It should be noted that the present invention also provides for a pre-positioning notch for the clasp 10 according to the first embodiment shown in the figures 1-9B In this case, the lateral face 36 of the movable part 6 could be provided with grooves along the slot 13. The grooves may preferably be in the shape of hollow half-moons, as in the case of the notching 115 of the clasp shown in the figures 10-18B . A ball ratchet could be located in the first stringer 8, possibly in a housing in orthogonal orientation formed in a suitable bulge which could be located next to (in longitudinal direction) the bulge 31.

[0117] Once the length has been adjusted as desired by the wearer, the pressure on the pusher 116 can be released, allowing the locking shaft 107 to move under the action of the spring 29, thus enabling the locking rod to be inserted into the corresponding recess of the first notch 114. The rod 117 will fit precisely into this recess, as the moving part 106 has been pre-positioned by the second notch 115 and the ratchet 135. The length adjustment device will then return to its resting position as shown in the figure 18 A .

[0118] It can also be specified that the movable part 106, when unlocked, cannot leave its housing between the longerons 108, 109, because the locking shaft also functions as a stop structure, against which the lug 154 abuts when a carrier pushes the movable part towards the opening at the free end of the two longerons 108, 109 (on the right in the figures 18 A et 18 B ). Towards the opposite end in the longitudinal direction, the stroke of the moving part 106 is limited by the base 137 of the second blade 122.

[0119] Some features of the clasps shown in the figures will be summarized below. In these clasps, the bracelet length fine adjustment device 5; 105 is associated with an "inner" or "second blade" 22; 122, which is arranged to fit between two ribs 21.1, 21.2 of a main or first blade 22 when the clasp is closed. In both clasps, the adjustment device 5; 105 is integral with said second blade 22; 122. This is made possible by the arrangement of at least part of the adjustment device 5; 105 above the common surface 19a, 19b of the clasp blades. The second blade 22; 122 includes, in particular, bulges 31, 32; 131, 132, in which one or more structural elements of the adjustment device 5; 105 are arranged. Thanks to this raised arrangement, it is possible to attach and / or associate the adjustment device 5, 105 to the inner blade 22; 122.

[0120] Another distinctive feature of the clasps is that the inner blade 22; 122 itself comprises two longitudinal members 8, 9; 108, 109, between which the movable part 6; 106 is arranged. This also allows the adjustment device to be connected to the inner blade. Preferably, the locking member 7, 107 is housed in a recess arranged on either side of a space between the two longitudinal members. In other words, one part of the recess 31, 131 is arranged on the first longitudinal member 8, 108, and a second part of the recess is arranged on the second longitudinal member 8, 109.

[0121] It can be specified that the actuation member 16; 116, intended to be activated by a user to finely adjust the length, is integral and preferably coaxial with a locking shaft 7; 107 which carries the locking structure 17; 117, arranged to cooperate with a notch 14, 114 of the moving part, in order to allow the locking of an adjusted length and the adjustment of the length following an unlocking.

[0122] In the clasps shown, the locking shaft 7; 107 has an orthogonal orientation. The bulges 31, 32; 131, 132 have recesses or tubes in which the locking shaft is housed. The locking shaft 7, 107 may comprise successive sections of different diameters, in order to create bearing surfaces, for example, for a spring, and / or to allow the shaft to be housed in its recess, to interact with the moving part and / or to be connected to an actuating member 16; 116.

[0123] The locking shaft, including the actuating member and the locking structure 17, 117, can be more generally referred to as the locking member 7, 107.

[0124] In the clasps shown, the orthogonal arrangement of the shaft 7, 107 and the tubes 31, 32; 131, 132 in which it is housed in elevation relative to the common surface 19a, 19b of the first and second blades, coincides with the orthogonal orientation of the first fastening member 1 and / or with the orientation of the tubes housing at least part of the locking means 3.4, 3 of the clasp and / or of the second fastening member 2. As can be clearly seen in figures 1 , 3 , 10 , And 12Several longitudinal devices or subassemblies of the clasp are characterized in said orthogonal orientation, said longitudinal subassemblies being thus parallel to each other. For example, the locking shaft 7, 107 is parallel to the first fastening member 1 and / or to an axis thereof. According to another example, the shaft 7, 107 is parallel to a cylinder 3.4 of the locking means 3.4, for example, to the transverse cylinder thereof. According to one example, the shaft 7; 107 is parallel to a tube or shaft 2.4, which forms part of the second fixing member 2. According to one embodiment, one or more of the following selected from: the rod 1 of the first fixing member, the cylinder or shaft 3.4, and the tube or shaft 2.4 are arranged in elevation and / or above the common surface 19a, 19, (19c), of the first, second and, where applicable, third blades 20, 22, 23, when the clasp is closed.

[0125] The features discussed above give all the clasps shown a compact and aesthetically pleasing appearance. This applies particularly to the three-blade clasp, in which the two lateral blades 22, 23 carry, respectively, the length adjustment device 5, 105 and the clasp locking device 3, and / or respectively the adjustment device 5, 105 and the second fastening member 2. In a three-blade clasp, the blade carrying the clasp locking / closing means descends into the closed position after the blade carrying the length adjustment device when the clasp is closed. The third blade 23 is preferably arranged to block and / or lock the second blade when the third blade, carrying locking means 3, is brought into the closed position.

[0126] In one embodiment of the invention, the movable part 6 is pivotally mounted on the blade 22 carrying the length adjustment device 5. This feature can also be implemented in a clasp having a different configuration, for example, with the adjustment device 5 mounted on the main or "outer" blade 20. In the embodiment shown, the locking member 7 or a portion 15 thereof functions as a pivoting axle for the pivotally housed movable part. This is made possible, for example, by a longitudinal slot 13 disposed in the movable part, and / or the arrangement of the grooves of a toothed / notched portion 14 along and / or directly adjacent to said slot.

[0127] According to the invention, an axis of said locking shaft 7 constitutes the pivot axis of said moving part 6.

[0128] A person skilled in the art will also observe that, due to the guidance of the locking shaft 7 through a slot in the moving part 6, the shaft 7 is arranged lower (in the direction of a vertical axis) than in the case of the clasp shown in figures 10-18B , where the locking shaft 107 passes over the moving part 106. For this reason, the first blade 20 of the clasp of the embodiment of the figures 1-9B may have notches 39.1, 39.2, to accommodate at least part of the locking shaft housing when the clasp is closed. More specifically, the notches may accommodate lateral extensions 33, 34, preferably tubular, of the locking shaft housing 7. Even if, in this case, the shaft 7 is positioned less elevated relative to the general plane of the clasp, the axis of the shaft 7 preferably remains above the common surface 19a, 19b of the first and second blades.

[0129] A difference in the clasps shown at figures 1-9B And 10-18B , respectively, is that in the first case, the locking shaft 7 and the locking structure 17 are in the same horizontal plane ( figures 9A-9B ), whereas in the second case, the locking structure 117 is not arranged in the same horizontal plane as the locking shaft 107.

[0130] Preferably, in the first case, the locking shaft 7 and the locking structure 17 are coaxial. For example, both 7 and 17, or at least one of them, is cylindrical. In the second case, the axis of the shaft 107 is preferably parallel to the locking rod 117.

[0131] A person skilled in the art will not encounter any particular difficulty in adapting the content of this disclosure to their own needs and implementing a clasp, particularly for a timepiece. As mentioned, the length adjustment device according to the invention can be adapted to other types of clasps, particularly for wristwatches.

Claims

1. A bracelet clasp (10) for bracelets of the type comprising first and second free ends, the clasp (10) enabling an adjustment of a length of the bracelet, said bracelet comprising: - first and second attachment members (1, 2) of the bracelet intended for being connected to said first and second free ends, respectively, of the bracelet, said attachment members (1, 2) being movable relative to one another between at least one open position and a closed position, of service, in which they are closer to one another than in the open position, the clasp comprising: - locking means (3) that make it possible to open and close the clasp; - a first support (22) having a device for adjusting the length (5) of the bracelet, said device for adjusting the length comprising a mobile piece (6) to which one of the two attachment members (1, 2) is secured, wherein said mobile piece (6) is pivotably mounted on said first support (22), wherein an axis of a locking element (7) constitutes the pivoting axis of said mobile piece, characterized in that the locking element (7) is provided for being moved axially in order to unlock the device for adjusting the length (5) and to allow a length adjustment of the bracelet.

2. The clasp (10) according to claim 1, characterized in that said support (22) comprises two side members (8, 9), separated by a central longitudinal opening (30), and in that said mobile piece (6) is provided so as to pivot in said central opening (30).

3. The clasp (10) according to any one of the claims 1 and 2, characterized in that said length-adjustment device (5) comprises said locking element (7) comprising a narrower section (15) and in that the size of the narrower section (15) substantially matches the height of a longitudinal slot (13) arranged in the mobile piece (6) and allowing the locking element to pass through said longitudinal slot.

4. The clasp (10) according to claim 3, characterized in that said locking element (7) comprises a bulge (17) with a shape that complements the shape of one of the recesses of a serrated portion (14) arranged in the mobile piece (6) along said longitudinal slot (13).

5. The clasp of claim 1, characterized in that the locking element (7) is the only structural element that connects the mobile piece (6) to the support (22) and in that the locking element (7) operates as a locking structure for blocking the mobile piece (6) in a position defining an adjusted fine length along the longitudinal direction of the bracelet.

6. The clasp of claim 1, characterized in that the device for adjusting the length is arranged to allow length adjustment independently of whether the clasp is in the open or in the closed position, and to allow the adjustment of the length of the bracelet even while keeping a wristwatch provided with the clasp of the invention on the wrist.

7. The clasp (10) according to claim 1, characterized in that said locking element is placed in a direction orthogonal to the length direction of the bracelet.