Abstract:
A decorative clasp closes by magnetic action, and can be worn on the front, i.e. at the throat or beneath the throat. The clasp allows the loop size of the jewelry article to be adjusted to suit the wearer&#39;s preferences. A pair of arcuate arms are joined at a pivot member, and close magnetically to form a generally oval shape.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to jewelry clasp in which one end of a string or strand of beads, i.e., a necklace or bracelet, is attached to the clasp, and a hinged oval loop or bight closes over the string or strand near the other end, i.e., between two beads on the jewelry article. The invention is more specifically directed to a decorative clasp which closes by magnetic action, and which can be worn on the front, i.e. at the throat or beneath the throat, and which allows the loop size of the jewelry article to be adjusted to suit the wearer&#39;s preferences. 
     Typically, clasps for closing a necklace or similar string of beads, pearls, or gemstones employs a two-part mechanical clasp of which one part is attached to one end of the string or strand, and the other mating part is attached to the other end. These are usually mechanical closures, although in some cases magnetic action has been employed. One example of a magnetic clasp for a necklace is discussed in Fuhrman et al. U.S. Pat. No. 7,334,433. A magnetic clasp is also discussed in Ito U.S. Pat. No. 6,349,568, in which the clasp is of the center-bend type, formed of a pair of arcuate members that pivot from one end attached to the end of the necklace, with the mouth of the clasp being closed by magnets at the free ends of these members. Alternatively, the clasp may be formed of a soft resin such as polyethylene folding in half and closed magnetically. 
     An ornamental closure or hook for latching one end of a strand of pearls at a place between two pearls near the other end is discussed in Ito U.S. Pat. No. 7,024,886. This may be worn in front. However, the device requires mechanically placing a hook in the space between two pearls. Other decorative front-mounted pearl necklace shorteners have appeared as well, e.g., in Bohlinger et al. U.S. Pat. No. 3,225,565. These typically require a great deal of finger dexterity to attach and release, and often cannot provide the desired appearance to match the look of the string of beads or pearls. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide a jewelry article, and a magnetic action jewelry clasp arrangement that avoid the drawbacks of the prior art. 
     It is another object to provide a jewelry clasp arrangement that opens and closes easily, using magnetic action, which does not require a high level of dexterity to open and close, and which has an attractive look that enhances the appearance of the jewelry article. 
     It is a more specific object to provide a pair of simple and straightforward clasp that permits shortening of a strand of beads, i.e., pearls, gemstones, or artificial spheres or other shapes, so that the same string or strand can be worn at different lengths to suit the occasion and the desires of the wearer. 
     In accordance with one aspect of the present invention, a jewelry item is formed as a plurality of bead members strung in line upon a flexible cord, and a jewelry clasp is attached onto one end of the flexible cord. The clasp closes over a narrow space or valley defined between successive ones of said bead members. In embodiments of this invention the clasp is formed of a first arm member that has an eyelet that is adapted to receive said one end of the cord, so it can be attached, i.e., tied, to the one end of the string or strand. A first magnet is disposed at a distal end portion of this first arm member. A second, arcuate arm member extends distally from the first magnet, and a pivot member is situated at the far or distal end of this second, arcuate arm member. A third, arcuate arm member has a pivot end joined to this pivot member, and the third arm member extends proximally therefrom, i.e., back towards the first magnet and the first arm. In this construction, the third arcuate arm member is adapted to open out from said second arm member and close towards said second arm member. A second magnet is affixed at a proximal end of the third arcuate arm member and is positioned to mate magnetically against the first magnet. Favorably, the second and third arcuate arm members bow out in respect to one another to define an oval-shaped loop that engages the strand of pearls or beads when said second magnet engages and closes against the first magnet. 
     In some embodiments, the third arcuate arm member, i.e., the movable arm can be disposed behind the second or fixed arcuate arm member, so that the clasp opens and closes at the rear, i.e., towards the wearer&#39;s neck. In other preferred embodiments, the third or movable arcuate arm member is disposed in front of the second arcuate arm member, so that the clasp opens and closes at the front, i.e., the side away from the wearer&#39;s neck. The clasp can be adorned with a first decorative leaf member disposed upon the first arm member and/or may also have a second decorative leaf member disposed upon the movable or third arm member. The leaf member may be designed to represent foliage, or a blossom, or any other shape, or may be a non-representational abstract design, depending on the tastes of the jeweler and/or the wearer. The second decorative leaf member can extend proximally over the second magnet, and thus may conceal much of the closure parts of the clasp. 
     Favorably, the first and second magnets may each include a generally cylindrical socket in which a permanent magnet member is fitted. 
     Terms such as bead, string, leaf, and oval, as used in the description and in the claims, should be interpreted broadly, and not limited to the illustrated embodiment. 
     The above and many other objects, features, and advantages of this invention will be more fully appreciated from the ensuing description of a preferred embodiment, which is to be read in conjunction with the accompanying Drawing. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  is a perspective view of a jewelry item, in the form of a strand of round beads, which may be pearls, or may be gemstones, ceramic beads or other items strung on a flexible string, wire or cord, and featuring a magnetic clasp according to an embodiment of the present invention. 
         FIG. 2  is a perspective view thereof showing the back side of the clasp. 
         FIG. 3  is a side perspective view of the clasp of this embodiment. 
         FIG. 4  is a front perspective view of the clasp in an open position. 
         FIG. 5  is another perspective view thereof. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With reference now to the Drawing,  FIG. 1  shows an item of neck-worn jewelry in the form of a necklace, i.e., string or strand  10  of generally spherical beads  11 , which are strung in line on a flexible cord e.g., a string or wire. In this embodiment, there are smaller spacer beads  12  included between the second and third beads  11 , between the fourth and fifth beads  11 , and so forth. In many embodiments, the necklace would be constructed with a knot formed between successive beads, and there is a generally V-shaped valley or recess defined between any two successive beads. As shown in  FIG. 1 , there is a decorative clasp  14  that is attached onto one end of the necklace  10 , and this clasp attaches over the necklace between any two successive beads  11  at or near the opposite end. In the illustrated embodiment, the clasp is fastens over the necklace a few inches from the end, so that the necklace is worn up on the neck with the clasp  14  visible at the front, that is, with the decorative clasp  14  visible on the wearer&#39;s neck. The remainder of the necklace hangs down as a single strand, i.e., as a pendant. 
     Details of the construction of the magnetic clasp  14  can be seen in the remaining views, namely,  FIGS. 2 to 5 . 
       FIG. 2  shows the reverse of the necklace or strand  10  and clasp  14 . The clasp  14  has an eyelet  16  at one end of a first more-or-less linear bar or arm  18 , and the eyelet  16  serves as a point of attachment for the cord or wire at one end of the strand  10 . The first arm  18  extends distally, i.e., away from the end of the strand  10 , and a first magnet member  20  is affixed at the distal end portion of the arm  18 . Then a second, curved (that is, arcuate) arm  22  continues distally from the magnet member  20  and ends at a hinge or pivot member  24 . 
     Turning now to  FIGS. 3 to 5 , it can be seen that a third, curved (i.e., arcuate) arm  26  is pivotally attached at one end to the second curved arm  22  at the pivot member  24 . This allows the third arm  26  to swing in and out between a closed position ( FIG. 2 ) and an open position ( FIGS. 3 ,  4 , and  5 ). As especially in the closed position, the third arcuate arm  28  is seen to extend back, i.e., proximally, from the hinge or pivot member  24 . There is a second magnet  28  positioned at an end portion of the arm  26 , and in the closed position of the clasp  14  the two magnets  20  and  28  magnetically engage and grip one another. However, the magnets can be pulled apart easily by the wearer wishing to put on the jewelry article, or take it off, or adjust it. 
     As seen in  FIG. 2 , the two curved arms  22  and  26  define a more-or-less oval shape that fits into the valley or gap between successive beads  11 ,  11  when the clasp  14  is closed. The gentle curvature here lies against the beads and does not scratch or abrade them. In this embodiment, the clasp  14  opens to the front, but in some other embodiments the clasp can open to the rear. 
     As seen in  FIG. 1  and also in  FIGS. 3 ,  4 , and  5 , the clasp  14  includes decorative leafwork, i.e., flat or shallow three-dimensional ornamental members covering the clasp mechanism at the front of the clasp  14 . A first decorative leaf member  30  is disposed at the front or side of the first arm member  18 , and in some embodiments the arm member  18  can be unitarily formed with the leaf member  30 . Here, the magnet  20  is shown at the distal edge of the leaf member  30 . Another leaf member  32  is formed on the front of the third or movable curved arm  26  and extends over the hinge or pivot member  24 , the curved arm member  26  and the second magnet  28 , so that these are concealed behind the leaf member  32 . In some embodiments, the arm member  26  can be formed unitarily with the ornamental leaf member  32 . As seen in  FIG. 1  the two leaf members  30  and  32  combine to make a single visual impression. 
     In the illustrated embodiment, the leaf members  30 ,  32  are in the form of a floral design, but in other embodiments, these can be made to represent foliage, twigs, animal shapes, or arbitrary and abstract non-representational designs, depending upon the tastes and preferences of the jeweler. 
     In the present embodiment, the clasp  14  is formed of a sterling silver, but in other embodiments, other materials can be used. The materials may include a plastic resin, a metal, or a ceramic, for example. 
     Here, the magnet members  20  and  28  are in the form of shallow cylindrical cups (e.g., formed of sterling silver or other jeweler&#39;s material) with a small disk-shaped permanent magnet contained within it. 
     The clasp  14  is here shown used with a strand  10  formed of generally spherical beads  11  of more or less uniform size, with smaller size spacer beads  12 . However, the clasp  14  can be used to advantage with beads of non-round shape, or with strands of beads or pearls that are of varying size and/or type. The clasp  14  can be used with necklace in the form of a double strand. 
     While the invention has been described in respect to a preferred embodiment, the invention is not limited only to that embodiment. Rather, the scope and spirit of this invention is to be defined in accordance with the appended claims.