Abstract:
A watch bracelet includes two straps ( 12, 14; 46, 48 ), designed to be fixed to a watch case ( 24, 44 ) at one of the ends thereof, characterized in being provided with a lentiform loop ( 18, 40, 58 ) fixed thereto.

Description:
TECHNICAL FIELD 
     The present invention relates to watch bracelets. They are generally made up of two strands each fixed by their ends on one hand to the case and on the other hand to a part of a clasp. The latter is arranged so as to allow opening and closing of the bracelet, enabling the placement, removal and maintenance of the watch on the wearer&#39;s wrist. 
     BACKGROUND OF THE INVENTION 
     The strands of the bracelet are made in a flexible material, such as leather or plastic, or in a hard material, for example metal or ceramic, in the form of links mounted hinged to each other. 
     The bracelet can also be made of two rigid arms in a circular arc, hingedly connected to the case. 
     The clasp can in particular be formed, secured to one of the strands, by a buckle and a tongue, which engages in holes comprised by the other strand. It can also be of the deploying type, comprising one or two pairs of hinged arms, kept closed by a locking member. The functional structure of these different types of bracelet and clasp are well known by one skilled in the art, which is why they will not be described in further detail as to their maintenance function. 
     The function of the bracelet is therefore generally to ensure maintenance of the watch on the arm of the wearer. Known, however, are bracelets on which plates are mounted bearing written information, for example a calendar. Also known are bracelets with links whereof at least one is hollow and is used to house objects with small dimensions, for example contact lenses. 
     Document CH 682′290 describes, for example, a bracelet provided with a housing in which an object such as a magnifying glass can be arranged. The magnifying glass is removable and can easily be moved away. Moreover, document FR 2,599,521 relates to a watch provided with a mirror mounted pivoting on the case and covering the display. 
     Document U.S. Pat. No. 5,601,222 concerns a wristwatch in which a magnifying glass is integrated to one of the strands of the bracelet. All leads one to think that this is a Fresnel-type magnifying glass, given its shape and dimensions. A magnifying glass of this type is generally made in plastic. In the described embodiment, the dimensions of the magnifying glass are certainly large, but the risk is great that the magnifying glass will deform and scratch, then no longer being able to perform its function. 
     In document U.S. Pat. No. 1,874,984, a magnifying glass is secured to a wristwatch case using a small chain. This small chain risks catching, making wearing the watch somewhat uncomfortable. Lastly, the German utility model DE 201′06′021 describes a watch provided with a magnifying glass mounted on the cap of the clasp or on the case. The magnifying glass arranged on the cap of the clasp seems to be made up of a cylinder whereof the diameter is smaller than the thickness, not able to ensure an observation function. 
     Very top-of-the-line watches sometimes comprise identification codes etched on the bottom of the case. These are very difficult to read, since they must be discreet in order to avoid effecting the esthetics of the product. The presence of a magnifying glass makes it possible to verify this information, but also to examine the fineness of the decorations with which the watch is provided in detail. 
     BRIEF DESCRIPTION OF THE INVENTION 
     One aim of the present invention is to offset the drawbacks cited above, while allowing the wearer of the watch to see objects or signs with small dimensions. 
     To this end, the watch bracelet comprises two strands designed to be secured each by one of its ends to a watch case and a clasp attached to the strands by their other end, the clasp being able to occupy an open position and a closed position. The bracelet is provided, according to the invention, with a magnifying glass of lenticular shape fixed thereto. 
     “Magnifying glass of lenticular shape” refers to a magnifying glass in the form of a lens, i.e. whereof the thickness at the center is substantially greater than that of the periphery. The ratio is at least equal to 2:1. The periphery can, of course, end with a beveled edge. 
     Advantageously, the bracelet also comprises a protection member arranged so as to cover the magnifying glass when the clasp is closed. 
     In a first variation, this clasp can comprise at least two arms hinged to each other using a hinge integral with one of the two ends of the two arms, and a body integral with the other end of the arm, the magnifying glass being mounted in this body. 
     In another variation, the magnifying glass is mounted in one of the strands of the bracelet, the other strand forming the protection member. 
     The strand on which the magnifying glass is mounted can also be rigid and the magnifying glass mounted hingedly on this strand. Advantageously, the magnifying glass is mounted on the strand via a spherical structure allowing orientation of the magnifying glass by rotation and tilting. 
     In order to avoid scratching of the magnifying glass, it is advantageously made in sapphire. 
     In another variation, the clasp comprises a median arm and two end arms, the median arm being hingedly connected to the two end arms. The magnifying glass is fixed to the median arm and the end arms comprise, in their portion adjacent to said magnifying glass when the bracelet is closed, a flexible film forming a protection member. 
     The present invention also concerns a watch provided with a bracelet as defined above. This watch also comprises a case. The case and the clasp comprise male members for one, female members for the other arranged to be engaged in each other. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be better understood upon reading the description which follows, provided as an example and done in reference to the drawings in which: 
         FIGS. 1 to 3  and  3   a  illustrate, diagrammatically, four embodiments of the invention; 
         FIG. 4  illustrates an embodiment in which the magnifying glass is mounted with a certain rigidity on the case; 
         FIGS. 5   a  and  5   b  present a variation of the clasp equipping the watch of  FIG. 4 ; 
         FIGS. 6 and 6   a  illustrate a marquise watch provided with a magnifying glass; and 
         FIGS. 7 to 9  show a top view and side view, in the unfolded and folded positions, respectively, of another embodiment of a clasp according to the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  illustrates a clasp for a watch bracelet of the deploying buckle type and designed to equip a bracelet provided with flexible strands, for example in leather. This clasp comprises a body  10 , two arms  12  and  14  mounted hingedly each at one of the ends of the body  10  and a buckle  16  mounted hingedly on the arm  12 . 
     The body  10  comprises two bars  10   a  and  10   b  connected to each other via a rod  10   c  and by arbors not visible in the drawing and which ensure the pivoting of the arms  12  and  14  on the body  10 . 
     The arm  12  presents a structure of the tuning fork type, with two bars  12   a  and  12   b  free at one end and connected to each other in the part of the arm hinged on the body  10 . The bars  10   a  and  10   b ,  12   a  and  12   b  are arranged so as to allow notch interlocking of the arm  12  in the body  10 . The arm  12  comprises, at its end opposite its hinge, two fingers  12   c  and  12   d  oriented perpendicularly to the arms  12   a  and  12   b  designed to receive a buckle  16  in which one of the strands of the bracelet is fixed. 
     The space between the bars  10   a  and  10   b  is defined such that the bars  12   a  and  12   b  and the arm  14  can be housed there. 
     The arm  14  has, in its median portion, a cylindrical opening in which is arranged a magnifying glass  18 , fixed, for example, by sticking. The end of the arm  14  opposite its articulation with the body  10  is provided with two fingers  14   a  and  14   b  arranged laterally and aligned with each other, designed to receive the end of the second strand of the bracelet opposite the case. 
     When the clasp is open, as shown in  FIG. 1 , the magnifying glass  18  can be arranged above the back of the watch, in order to look at its components, if the bottom is transparent, for information appearing on the bottom of the case, or also an object arranged on this bottom, for example a stamp, a medal, a jewel, etc. 
     When a watch equipped with a clasp of this type is put on the arm, the wearer begins by folding the arm  14  down such that it is engaged between the two bars  10   a  and  10   b  of the body  10 , then the arm  12  is folded, the bars  12   a  and  12   b  clipping into the body  10 , while the end of the arm  12  and the buckle  16  covers the arm  14  and keeps it in place. In this position, the strand of the bracelet engaged in the buckle  16  covers the magnifying glass  18  and protects it, thereby forming a protection member. 
     In the embodiment of  FIG. 2 , one finds the body  10  and the arms  12  and  14 . In this embodiment, the arms  12  and  14  both have a turning-fork structure, which clips into the body  10 . The latter is provided, in its median part, with a cylindrical opening in which the magnifying glass  18  is fixed.  FIG. 2   a  shows, enlarged and in cross-section, the part of the body  10  supporting the magnifying glass  18 . As shown by this figure, the body  10  has a shoulder  10   d  in the form of a truncated cone, on which the magnifying glass  18  rests. The wall of the body  10  is provided with a tapping  10   e  through which a ring  20  is screwed, which maintains the magnifying glass  18  in place. In this variation as well, the strand of the bracelet engaged in the buckle  16  covers the magnifying glass in the closed position of the bracelet, protecting it. 
     The magnifying glass  18  can be realized in any type of transparent material, but advantageously in sapphire, such that it does not scratch. 
     In the embodiment illustrated in  FIG. 3 , the bracelet comprises a strand  22  supporting the buckle  16 . The strand  22  comprises, illustrated in  FIG. 3   a , a core formed of two sheets  22   a  and  22   b  in a semi-rigid material, welded to each other and provided with a cutout  22   c . The magnifying glass  18 , with a larger diameter than the cutout  22   c , is housed there and maintained in place. The core is coated with two sheets of leather  22   d  and  22   e , giving the bracelet an elegant appearance and providing comfort for the wearer. Also in this embodiment, the end of the second strand of the bracelet covers the magnifying glass  18 . 
       FIG. 4  shows, from the side, a watch comprising a case  24  and a bracelet  26 , which comprises two strands  28  and  30  and a clasp  32 . The latter part comprises a central body  34  and two pairs  36  and  38  of arms identified by the letters a and b, hinged in a bend identified by the letter c, forming an articulation. The pairs of arms are hingedly secured to the body  34  by one end and to the strands  28  and  30 , respectively, by the other end. 
     The arms  36   a  and  36   b  of the pair  36  comprise, beyond their bend  36   c  forming the articulation, two fingers  36   d  and  36   e  which tend to separate from each other when the arms open. The structure is the same, symmetrically, regarding the arms  38   a  and  38   b.    
     The case  24  comprises housings  24   a  and  24   b  in which the fingers  36   d  and  36   e ,  38   d  and  38   e , respectively, are engaged. Once they are separated, they are kept in their respective housings  24   a  and  24   b.    
     The central body  34  comprises a ring  39  inside which a magnifying glass  40  is mounted. The fastening of the magnifying glass  40  in the ring  39  can be done in different ways, for example by sticking or mechanically as explained in reference to  FIG. 2 . 
     One will note that in the case where the strands  28  and  30  are of the hinged link type, they tend, by their weight, to separate the two arms a and b of the pairs  36  and  38 , thus maintaining them in the housing  24   a . In this way, the magnifying glass  40  is positioned on the case  24 , the bottom thereof being able to serve as a support to arrange an object to be examined there. It is, of course, also possible to admire the structure of the movement inasmuch as the bottom is transparent, or to read information etched on the bottom, for example an identification code. 
     The manner in which the arms  36  and  38  are engaged on the case  24  ensures satisfactory positioning. It is nevertheless possible to move the magnifying glass  40  laterally, by pressing on the arm  36   a  or  38   a , such that the surface to be observed can thus be swept. 
     In this embodiment, the arm  36   b  could be extended so as to cover the magnifying glass  40  and thus form a protection member. 
       FIGS. 5   a  and  5   b  present a variation of the clasp equipping the watch of  FIG. 4 , in its part comprising the central body  34  and the arms  36   b  and  38   b , seen from the side and in cross-section, respectively. In this variation, the central body  34  is formed of two shells  34   a  and  34   b  defining a housing between them whereof the side walls comprise rack structures  34   c  and  34   d . A strip spring  42  is arranged in the housing. The arms  36  and  38  support, at their end near the body  34 , two fingers bearing the references f and g, the free end of each of which is provided with a head bearing references h and i. The fingers f and g of a same arm are coaxial and arranged so as to cooperate respectively with the teeth of the racks  34   c  and  34   d . The heads h and i are arranged inside the housing, bearing against the spring  42  which tends to push the fingers into the spaces between the teeth of the racks. In this way, the distance between the arms  36   a  and  38   a  can be adjusted. The more the ends of the arms  36   a  and  38   a  near the body  34  are close together, the closer the magnifying glass  40  is to the bottom. One will note that it is also thus possible to adjust the length of the bracelet very simply. 
     The watch illustrated in  FIGS. 6 and 6   a  is of the marquise type. It comprises a case  44  and two rigid arms  46  and  48  mounted hingedly on the case  44 , using spring hinges  50  and  52 , tending to bring them closer to each other. As shown in  FIG. 6   a , which is an enlarged side view of the end of the arm  46 , the latter is provided with an opening  46   a , at its end opposite the hinge  50 , in which is found a piece  54 , of oblong shape. The piece  54  comprises a central portion  56  provided with a magnifying glass  58 , a stem  60  at one of its ends, which is provided with a sphere  62 . The opening  46   a  is adjacent to a slit  46   b  in which a housing  46   c  is formed receiving the sphere  62 . 
     The opening  56   a  can be replaced by a housing whereof the bottom wall is situated on the convex side of the arm. In this way, when the magnifying glass  58  is retracted, it is protected by this wall. 
     The piece  54  can advantageously be held in the housing  46   a  by a ball housed in the strand  46  and cooperating with a recess formed in the framework of the central portion  56 . 
     The portion  54  can be released from the arm  46  and brought into the interval between the two arms  46  and  48 . In a variation which was not shown, the portion  54  can be pinched between the two arms, in order to be well-positioned. It is also possible to turn it practically in any position, thanks to a ball pivot connection ensured by the sphere  62  and the housing  46   c.    
     The magnifying glass  58  is in a truncated lenticular shape, to fit the drop shape of the opening in which it is housed. 
     In this embodiment, the arm  48  could also be provided with a magnifying glass, such that the assembly thus formed constitutes a higher performance optic. By arranging the magnifying glass s such that they are oriented along an axis parallel to the bottom of the watch, it is also possible to realize a small long view, usable in the theater for example. 
     In order to protect the magnifying glass and avoid it becoming dirty, the bracelet can, furthermore, be equipped with a cover or a removable sleeve, removed during use. 
     Another solution allowing good protection of the magnifying glass is shown in  FIGS. 7 to 9 . The clasp illustrated in these figures comprises three arms  64 ,  66  and  68  arranged in a chain and hinged to each other. These arms have shapes such that, when they are folded, they are substantially superimposed. The arm  64  is secured to a first strand  72  of the bracelet using a strip  70 . The arm  68  is provided with a buckle  74  in which a second strand  76  of the bracelet is engaged. The buckle  74  is provided with a finger, not shown in the drawing, on which the second strand hooks through one of the holes with which it is provided. In this way, the length of the bracelet can be adjusted. 
     The median arm  66  supports a magnifying glass  78  of lenticular shape, which can be stuck or gripped there as shown in  FIG. 3   a . Moreover, the arms  64  and  68  comprise, in their median portion, membranes  80  and  82 , made in leather for example. These membranes are arranged such that they cover the magnifying glass  78  when the arms are folded, i.e. in the position which they occupy when the clasp is closed, and therefore when the watch is worn. In this way, the magnifying glass is completely protected. 
     The watch bracelets which have been described can be the object of many other variations without going beyond the scope of the invention. Thus, the solutions shown in  FIGS. 1 to 4  could also be applied to a bracelet whereof the clasp only comprises one pair of deploying arms. 
     Other means can also be used to position the magnifying glass in reference to the case. These means can be directly connected to the bracelet. They can also be formed by a mobile piece integral with the case. 
     Rather than being secured using a ring, the magnifying glass could also have shapes such that it comprises its own fastening means. 
     In any case, a watch equipped with a bracelet of this type allows its user a complement enabling him to improve his observation conditions, close up or far away, under at least certain conditions.