Abstract:
This invention relates to a cufflink disassemblably coupled of its two pieces, one being a decorative member and another being a keeper element, with the aid of a spring clip. 
     The above assembling and disassembling are made quite easily and quickly by manual one touch fingering at a desired time, and once attached through button holes of the shirt&#39;s cuff which may be either one of double type or convertible type it is designed not to slip-off from the cuff, even when the cufflink brushes against a person and/or an object.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to an improvement of the cufflink. 
     2. Description of the Prior Art 
     The one-piece cuff-link conventionally used includes a decorative element and a link member integrally provided therewith, on which an engaging element displaceable in a right angle with an axial direction is attached. This engaging element is inserted into the button holes of the shirt&#39;s cuff, keeping its direction in a straight line, and then it is rotated in a direction at a right angle with the axial direction of the link member, so as to securely attach the cufflink onto the cuff. 
     The usage of such cufflink has a drawback that the insertion of the link into the button holes provided at a rear portion of the cuff, calls for an inconvenient manipulation since the link has been integral with the decorative member, the link has been easily rotated when it has contacted the wearer&#39;s clothing and the other objects, and such facts have caused the prior art cufflink to provide an unsightly appearance and to be subject to dropping-off from the cuff and becoming lost. 
     When the user has worn a convertible cuff shirt usually used for conventional cufflinks, a button has been located near one of the button holes on each cuff. The conventional cufflink as described above has not been able to hide such buttons and thus an unsightly appearance has been provided. 
     This inventor has proposed several inventions to overcome such drawbacks relating the cufflink, and has obtained the issued Utility Model Nos. 1253159, 1253166 and 1253167 on Oct. 31, 1978 in Japan. 
     The inventor has further proposed an improved version of the cufflink and has filed Japanese Utility Model application under Ser. No. 54-49013 on Apr. 13 and also filed its corresponding U.S. patent applications under Ser. No. 66,466 on Aug. 13, 1979. The latter has been issued as U.S. Pat. No. 4,242,776 on Jan. 6, 1981. 
     This invention is summarized as follows: 
     The cufflink has two units which are disassemblably assembled to one another through a pair of shirt cuff button holes. For assembly the outer end of the shank is inserted through an opening in the back of the decorative head element, pushed in further to deflect two springs inside the decorative head element and then the decorative head element is let go of, to lock the cufflink in an assembled condition. The shank is unitary with a keeper which has a recess in its inner face, for accepting and hiding from view the shirt button found beside one of the cuff button holes on so called &#34;convertible cuff shirts.&#34; For removal, the head and keeper are compressed and then relatively turned 90 degrees angularly of the shank. 
     SUMMARY OF THE INVENTION 
     The decorative head element of the cufflink has a hole in the back through which the head of the link shank is to be inserted. As the link shank head is inserted its semi-spherical surfaces engages free ends of a spring clip, temporarily pushing them back of a pair of projections which allows them to spread apart. As the head enters between the free ends, they snap into elongated grooves in opposite sides of the link shank head. Releasing finger pressure on the link shank allows the spring clip to resume a planar state, trapping the free ends in the grooves, between the link shank head and the pair of projections. To disassemble the cuff-link, the shank and decorative head element are squeezed together and turned 90 degrees about the shank axis and released. This action first untraps the free ends of the spring clip, then dumps them out of the grooves and then ejects the link shank head from the decorative head element. 
     The action of the spring clip is enhanced by providing its bridge with an out-of-plane arcuate central portion. In mounting the spring clip upon the inner face of the rear cover plate of the decorative head element, the arcuate portion is resiliently compressed into the plane of the spring clip by being lodged under an L-shaped bracket. Accordingly, the spring clip is resiliently loaded against the inner face of the rear cover plate. 
    
    
     BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS 
     FIG. 1 is a perspective view of the rear side of the decorative head element of the preferred embodiment of this invention; 
     FIG. 2 is a rear side view of the decorative head element; 
     FIG. 3 is a cross sectional view of the decorative head element, along line A--A in FIG. 2; 
     FIG. 4 is a cross sectional view of the decorative head element along line B--B in FIG. 2; 
     FIG. 5 is a perspective inside view of the rear cover plate of the decorative head element; 
     FIG. 6 is a perspective inside view of the case shell of the decorative head element; 
     FIG. 7 is a perspective view of the spring clip of the decorative head element; 
     FIG. 8 is a cross sectional view of the spring clip along line C--C in FIG. 7; 
     FIG. 9 is a perspective view of the securement plate of the decorative head element; 
     FIG. 10 is a side view of the link shank element; 
     FIG. 11 is a plan view of the link shank element; 
     FIG. 12 is a partial transverse cross sectional front view illustrating the engaged or locked condition of the decorative head and link shank elements; 
     FIG. 13 is a partial transverse cross sectional front view illustrating the beginning of the decoupling of the two elements; 
     FIG. 14 is a cross sectional view of the decorative head and link shank elements along line D--D in FIG. 13; 
     FIG. 15 is a partial transverse cross sectional front view showing a state when the decorative head element is rotated for 90° at the beginning of the decoupling of the decorative head element from the link shank element; 
     FIG. 16 is a cross sectional view of the two elements along line E--E in FIG. 15; 
     FIG. 17 is a partial transverse cross sectional front view showing a state shortly before the decoupling of the decorative head element from the link shank element; 
     FIG. 18 is a partial transverse cross sectional view showing a relationship between the head of the link shank element and the decorative head element; and 
     FIG. 19 is a side view showing another embodiment of the link shank element of this invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the drawings, there is shown a decorative member 1 which has a casing shell 3, in this embodiment in a generally rectangular box shaped with open back, into which a separate engaging link member shank element 2 is disassemblably attached, so as to form a cufflink. 
     The casing shell 3 of the decorative member 1 is made of a precious metal or any equivalent material and has a generally rectangular shape with an open back into which a rear cover plate 4 is attached by soldering or any other convenient means. The rear cover plate 4 is formed with a central annular hole 4a and at its inner surface also has a frusto-conical raised portion 4b surrounding the outer circumference of said central annular hole 4a. 
     Provided on an inside surface of the rear cover plate 4 is a pair of symmetrical wing projections 5 sandwiching said hole 4a. These projections are generally rectangular with an arcuate tip end and their root portions are disposed near the circumference of the hole 4a. 
     Provided on an inner surface of the rear cover plate 4 and in a widthwise direction at the top and the bottom of the hole circumference, sandwiching the hole 4a are a pair of L-shaped brackets 6,6 of which inner faces are curved partial inner cylindrical or arcuate walls 6a which continue to the circular hole 4a and tangs are provided with screw threads holes 6b. Each width of the L-shaped pieces is so determined to sandwich the spring clip free ends 7b later discussed, between said wings 5,5 and the brackets 6. A distance between the tang portions of the L-shaped brackets and the inner surface 4 is so determined to sandwich the later discussed spring clip 7. 
     FIG. 7 shows a convenient spring clip 7 for the present cufflink. This clip 7 has a generally eye-glass frame shape and is made of a resilient material, such as metal wire or any equivalent material. Side legs 7a,7a are generally symmetrically formed in U-shape and those have free ends 7b bent inwardly and an upper rim having an arcuate bridge portion 7c which arches downwardly, and which is also inclined outwardly at an angle to the plane of the remainder of the spring clip. In other words, the plane including said arcuate portion 7c and the plane containing the frame legs 7a,7a are not the same plane but angularly intersect as shown in FIG. 8. 
     This spring clip 7 is at its arcuate bridge portion 7c inserted within the space between the tang of either one of the L-shape brackets 6 and the rest of the spring clip surrounds the wings 5,5 at its U-shape legs 7a. Its free ends 7b are inserted between the wings 5,5 and both sides of the L-shape brackets 6,6 so as to sandwich both ends of the one of the L-shape pieces 6 at its tip ends. Therefore, the free ends 7b,7b are attached under a stored returning energy to close towards each other. 
     The slight gap between the tangs of the L-shape brackets 6 and the inner face of the cover plate 4 is wide enough only for accommodating the spring clip diameter. This causes the arcuate portion 7c to forcibly warp when the dent 7c is inserted between the selected L-shaped bracket 6 and the rear plate 4, and thus, the side legs 7a,7a are a force which presses them onto the rear face of the plate 4. 
     A securing plate 8 is fixed onto the inside the plate 4 after the securement of the spring clip 7. This securing plate 8 is generally formed in a rectangular shape and has toward the casing shell 3 a central frusto-conical projection 8a, which has a central cylinder 8b with a semi-spherical tip end oriented toward the rear cover plate 4. The frusto-conical projection 8a has its root diameter generally identical with the diameter of the annular hole 4a of the rear back plate 4, and the axes of both the cylinder 8b and the annular hole 4a generally coincide. The securement plate 8 has its lengthwise length equal to the horizontal distance between the ends of the L-shaped brackets 6,6 and has its widthwise dimension shorter than said distance. The securement plate 8 is fixed to the plate 4 by inserting screws 9 into the upper and lower holes 8c,8c in the lengthwise direction and threadably mating said screws 9 within female thread holes 6b,6b. In a state when the securement plate 8 is fixed, the tip ends of the cylinder 8b extend to an axial central portion of the annular hole 4a. 
     The link 2 has a structure as shown in FIGS. 10 and 11, which comprises a keeper 10 having a recess 10a for hiding a button in the shirt&#39;s sleeve cuff, and a shank 11 integrally provided at one end thereof, extending from its inner side on the same side of the recess 10a, at a certain angle forming a generally V-shape therebetween, as shown in FIG. 10. 
     The shank 11 has at its tip end a semi-spherical head 12 of which the cental forward end has a through hole 12a for receiving said cylinder 8b. Provided at opposite sides sandwiching the hole 12a, are grooves or slits 12b,12b with bottom walls which extend parallel with an axis of the shank 11 and upper and lower side faces which are perpendicular to the axis, thereby providing enough width and depth for receiving the free ends 7b of the spring clip 7. 
     The head 12 is formed semi-spherically but its circular curved face continues from a position generally identical with the side rim of the button hiding recess 10 side of said slits 12b. The root of the head has a plane surface perpendicular to the axis of the shank 11 and a smaller diameter arm continues therefrom to the shank 11. This arm 11a has a smaller diameter than the shank 11 and a length slightly larger than the thickness of the cloth of the sleeve cuff of the shirt. 
     Now, installation/assembly and removal/disassembly of the cufflink on and from a shirt cuff will be explained in more detail. 
     First, for wearing, the shank 11 is inserted into the button holes of the cuff and the head 12 is inserted into the circular hole 4a of the decorative head 1, keeping the slits 12b,12b of the head 12 opposite to the free ends 7b,7b of the clip spring 7. 
     The clip&#39;s free ends 7b,7b are forcibly spreaded along the semispherical surface of the head 12 and pushed upwardly, as shown in FIG. 13, and upon oppositely facing the slits 12b and the free ends 7b, the free ends 7b come into the slits 12b by their own stored energy and the cylinder 8b mates within the through hole 12a. 
     This state is shown in FIG. 13. In this state, a release of a pressure onto the shank 2 pushes back the shank 2, keeping the clip free ends 7b within the slits 12b mated, because of their pressure toward the rear cover plate 4, and then the head 12 returns to its original position of the clip&#39;s free ends 7b, together with said free ends 7b. In this state, since the free ends 7b are completely mated within the slits 12b, the head is not prevented from returning into the annular hole 4a, the clip free ends 7b never slip off nor come out from the slits 12b and the shank 2 never slip nor come out from the decorative member 1. This means that the decorative member 1 never rotate nor drop unless it is pushed or compressed toward the shank 2, since the clip free ends 7b are blocked from moving, by the circumferential wall of the annular hole 4a. This locking operation is accomplished by the work of one finger. 
     For removal of the cufflink, one must push the decorative member 1 toward the shank 2 to push the clip free ends 7b out from the annular hole 4a, and then rotate the head in either direction through 90° with respect to the link 2 from the state shown in FIG. 13 to the state shown in FIG. 15. Then, the clip free ends 7b,7b, respectively come out from the slits 12b,12b and contact the arcuate circumference of the head 12 angularly between the slits 12b,12b. 
     In this state, the clip free ends 7b,7b have two kinds of stored energy, or attracting energy therebetween and a repelling power to push the link 2 out. Since the head semi-spherical surface 12 starts a position generally identical with the side rim of the button keeper 10 side, the clip free ends 7b slide along the semi-spherical surface 12 of the head and the head 12 is, as a result, pushed out from the annular hole 4a to permit an easy de-coupling of the link 2. After that, the clip free ends 7b,7b take positions between the wings 5 and the L-shaped brackets 6. Thus, the assembling and the disassembling and attaching and detaching of the cufflink is quite easily accomplished at a desired time. 
     Heretofore, the embodiment has been explained for the usage for the convertible sleeve cuff having a button thereon which is hidden within the recess 10a of the keeper 10, but the cufflink is also compatibly usable with a conventional or double &#34;French&#34; cuff. The decorative head can be decorated with a fanciful design, symbol or symbols or alphabets such as the initials of the wearer&#39;s name, a house or family mark or a club&#39;s mark and the like. Those can be engraved on the decorative surface or attached with an adhesive-backed metallic sticker having those decorative signs. Those stickers can be selected by the wearer. 
     FIG. 19 shows another embodiment in which the shank 11 has a head 12 formed in an annular ring shape having its central hole 11b to prevent the link from rotating but its shape is arbitrarily selective as far as the same function is obtained. 
     The cufflink according to this invention has a simple design for manufacture but provides an esthetic outside view and a means for attachment and detachment by the work of one finger and it is usable for both convertible and double cuff shirts.