DESCRIPTION

The present invention refers to a method for the production of elongated elements for the manufacturing of a four-sided jewel, like, e.g., necklaces, bracelets, anklets, earring pendants and jewelry products in general. In particular, the present invention refers to a method for the production of elongated elements of the so-called "omega" type.

In jewel making, elements of elongate shape are widely used to manufacture, e.g. necklace chokers, bracelets, anklets, earring pendants, etc.

As it is well-known to those skilled in the art, the term "omega" commonly denotes a type of elongated element obtained by threading small rings of metal on a core, or by helically winding about the latter a flat strip or the like.

In general, in order to give greater distinctiveness to the jewel, the elongated element is machined, e.g. by means of surface machining or the setting of precious stones, at one side thereof, that will be facing outwards when the jewel is worn-on. hi said jewels there is the need to ensure a wearing option such as to keep the machined side always displayed. For this purpose, the elongated elements forming such jewels are manufactured with a squashed (flat) cross section, so as to prevent their winding up on themselves, hiding the machined side.

Moreover, the essentially flat plane allowed to make necklaces differently machined on two opposite sides, thereby allowing the choice between two different ornaments with a single jewel.

However, in such jewels it is not desirable that both sides be concomitantly visible; otherwise, the "double-face" effect characterizing them would be lost.

Current production methods do not allow to make a jewel with each of the four sides machined differently, so as to obtain a jewel that may be worn-on in four different configurations.

Ia fact, owing to the same considerations put forth above, the wearing option of such a jewel should be such that each of the four sides is individually displayed, preventing the jewel from unnaturally winding up on itself.

The machining methods according to the known art provide no alike wearing option, as not allowing to concomitantly attain flexibility such as to wear on the jewel, and

rigidity sufficing to keep only one side thereof displayed, without any winding up of the elongated element forming it.

Hence, the technical problem underlying the present invention is to provide a method for the production of an elongated four-sided jewel, overcoming the drawbacks mentioned with reference to the known art.

Such a problem is solved by a production method of elongated elements for the manufacturing of a four-sided jewel according to claim 1, and by the jewel according to claim 9.

The present invention provides several relevant advantages. The main advantage lies in that the machining method according to the present invention allows to obtain a four-sided jewel with a perfect wearing option, thereby allowing to use jewels with different machining onto the four sides, alternatively displaying only one of the latter during its use.

Other advantages, features and the modes of employ of the present invention will be made apparent in the following detailed description of some embodiments thereof, given by way of example and without limitative purposes. Reference will be made to the figures of the attached drawings, wherein: figures 1 to 7 refer each to a step of a first embodiment of the method of the invention, showing perspective views of the elongated element for the manufacturing of a four-sided j ewel in the various steps of its manufacturing; figures 8A to 8D are respective front views illustrating different configurations of the cross section of the elongated element; figures 9 and 10 are schematic illustrations of an inner core for the carrying out of the method according to the present invention; figure 11 refers to a step of inserting rings inside the core of figure 10, according to the embodiment of figure 1; figures 12 and 13 refer to a variant embodiment of a step of the method of the invention, showing a perspective view of the elongated element during the manufacturing thereof; and figure 14 shows by means of a perspective view a fastening device of a j ewel manufactured according to the method of the present invention.

A four-sided jewel produced with the method according to the present invention is manufactured from an elongated element, intended to be sectioned into a desired

number of longitudinal pieces, each one of a size suitable for the manufacturing of a desired jewel or portion thereof.

Such an elongated element, as it will be detailed hereinafter, is formed by a hollow coating of precious material inserted inside a core. With reference to figure 1 and according to a preferred embodiment, the coating is made by means of the welding of four foils 11, 12, 13, 14 of precious material, each of which will constitute one of the four sides of the end jewel, so as to manufacture a single plate, substantially formed by strips of different color or aspect.

Preferably, the four foils will have different aesthetic features. Not only can they differ for the color of the material used, but also for the surface machining; e.g., they could alternatively be diamond-ground or lapped, in order to have different aesthetic effects. Moreover, such a machining could be carried out in a subsequent step, directly on the finished elongated element.

It is also evident that it is not necessary for these foils to have different features: there may alternatively be used only two or three foils of different aspect thereamong, or at most four foils of the same kind.

Furthermore, in these cases the use of four distinct foils will not be necessary; the plate could equally be manufactured from three, two or only one foil, according to the number of different colors or machining. In the case of use of plural foils, the method according to the present invention provides that these be set side-by-side thereamong and longitudinally welded, so as to form a single plate 10 having plural colors or machining side by side thereamong. Such a welding defines respective weld lines 15, 16, 17 and 18.

Hereinafter, with reference to figure 2, the plate 10 thus made is folded onto itself and welded, so as to make a tubular element 20, which, once shaped, will constitute a hollow coating 30 of the elongated element, illustrated in figure 7.

The forming of the plate 10, in other words the folding thereof until obtaining the tubular element 20, is carried out by means of a roll forming machine, a device that will not be detailed hereinafter, as substantially already known in the state of the art. However, the Applicant has conveniently experimented that some specific contrivances in the forming steps allow to attain an improved result in the final manufacturing of the elongated element.

In particular, during the forming, and referring to figure 3, the tubular element is

initially formed so as to have a substantially elliptical cross-section, with the main axes 25 and 26 extending between opposed weld lines, 15, 17 and 16, 18, respectively, as illustrated in figure 4.

Referring to figure 5, only subsequently, by means of subsequent passes in the forming machine, the tubular element having elliptical section is transformed in an end four-sided hollow coating 30.

The hollow coating 30 has four substantially plane sides 31, 32, 33, 34, corresponding to the initially provided four foils 11, 12, 13 and 14, respectively.

This machining proves particularly useful so that the four-sided jewel, at least two sides of which look different, overall has an optimal appearance.

In fact, an extremely important feature is that each side 31, 32, 33, 34 be made by a corresponding foil, with an accurate separation in correspondence of the vertexes of the quadrangular section that the coating has owing to the four-sided configuration.

Therefore, in order to accurately make an end quadrangular shape, in which the separation among the sides corresponds to the weld lines 15, 16, 17, 18, the tubular element 20 is conveniently shaped first into an ellipsoidal shape with the main axes 25 and 26 extending between opposed weld lines, 15, 17 and 16, 18, respectively. All this allows to make a jewel with four distinct sides, having aesthetic aspects different thereamong. Referring to figures 8 A to 8D, in order to attain a displaying indifferently of only one of the four sides of the jewel, the end section should be such that the four sides 31, 32, 33, 34 of the hollow coating 30 shall be symmetrical two by two with regard to respective planes of symmetry 41 and 42.

Moreover, always in order to assure that only one side remains alternatively displayed during the use of the jewel, such planes of symmetry 41 and 42 are preferably orthogonal therebetween, so that during the use of the jewel only one side thereof remains in sight.

In addition, the sides of the hollow coating could be of a shape different from the plane one, e.g. have concave, convex shapes or other types of unevenness. The symmetry between the sides 31, 32, 33, 34 may also be limited to the orientation thereof, orientation meant as the direction normal to a median plane containing said sides of the hollow coating.

The method according to the present invention further comprises a drawing step, in

which, through square-section drawbenches having a square section, or anyhow a section of the desired end shape, them also known in the state of the art, the cross section is reduced to the desired size.

Referring to figure 7, the hollow coating 30 is then sectioned in form of rings 50; concomitantly, the method foresees a step of providing an inner core 60 that will be arranged internally to the hollow coating and, in particular, according to the present embodiment, inside said rings 50.

As already pointed out, the core 60 allows to give the mechanic features to the jewel, in terms of resistance as well as of flexibility. On the other hand, evidently the rings 50 need an element allowing to keep them together so as to form the jewel.

So that the jewels manufactured with the present method may be used displaying individually each of the single sides thereof, the elongated element forming it should have specific wearing option features. The jewels according to the known art do not allow such a wearing option, as essentially made to be worn on along only one, or at most two, of the sides forming it.

Instead, in order to ensure the wearing option of the jewel according to any one of the four sides thereof, the elongated element should have features of relatively high flexibility along the aforedefmed planes of symmetry 41, 42. By such a flexibility feature it is meant that the elongated element forming the jewel could undergo even elevated bending, e.g. those necessary to make a choker, along the planes of symmetry, whereas it may undergo only minimal displacements in other directions.

For this purpose, the core 60 provided according to the present method has it also flexibility features substantially identical on two orthogonal planes 61, 62. Said planes, analogously to what has been described with regard to the features of the hollow coating, will be defined as planes 61, 62 of maximum flexibility.

Then, the core is inserted inside the hollow coating 30, in particular, in the present embodiment, by threading the rings 50 in which the same coating has been sectioned. During this operation, in order to implement the hereto-described flexibility features, the insertion of the core 60 should occur so that the planes of symmetry 41, 42 of the coating be substantially aligned with the planes 61, 62 of maximum flexibility of the core.

This step may be attained by driving, on suitable guides not illustrated in figure, the core 60 internally to the coating 30.

Thus, the jewel exhibits greater flexibility with respect to the planes of symmetry 41, 42 of the coating, whereas it exhibits limited or nil flexibility along directions slanted with respect to said planes of symmetry.

Incidentally, the directions of maximum flexibility may also coincide with the direction orthogonal to the sides of the hollow coating.

Should said sides be not plane, the median plane thereof may be considered, and the orthogonal direction singled out thereon, as illustrated in the case of figure 7D. The flexibility feature described so far allows that wearing option of the j ewel allowing the displaying indifferently of a sole one of the four sides.

In fact, when considering, e.g., the manufacturing of a choker with the elongated element thus made, the displaying of a single side requires that the elongated element may bend on two substantially orthogonal planes. In order to prevent the j ewel from winding up on itself or anyhow be not perfectly laid onto the user's body, there should be inhibited the bending of the elongated element in directions slanted with respect to the two ones of maximum flexibility, besides from the twisting thereof.

Referring to figures 9 and 10, the inner core is manufactured by means of a plurality of circular elements 63 folded on themselves and set thereamong.

Thus, said circular elements could undergo motions the one with respect to the other exclusively along two planes substantially orthogonal therebetween, preventing instead motions in slanted directions.

The process for manufacturing such a core is substantially analogous to that used to make ornamental chains having alike mechanic features. E.g., among these chains there are those known by the names of foxtail, box, and cable.

Alternatively, this effect may also be made with a plurality of square-section strips of metal fabric, packed so as to internally engage the hollow coating.

Then, the structure formed by the coating 30, in form of rings 50, and by the core 60 is subjected to pressing along its entire longitudinal extension, to attain shape stability, surface evenness and, finally, mechanical resistance. It is important to observe that in the methods according to the known art, such a step of pressing is used also to carry out the alignment of the rings that form the coating.

In the method according to the present invention such an alignment is already carried out in the threading of the core inside the rings, since, should said step be carried out by pressing, it would not be possible to ensure the aligned arrangement of the planes of maximum flexibility and of symmetry. Moreover, during said step the coating 30 is conveniently pressed against the inner core 60, so that the latter internally engages the cross section of the coating.

Thus, the contour of the core 60 is at least partially squashed among the sides 31, 32, 33, 34 of the coating, and in particular "crimped" by the latter, thereby being stably integral thereto. Alternatively, such an effect may also be carried out with the use of a centrally hollow core, not illustrated in the figure, which however likewise extends to the walls of the inner coating, so as to ensure anyhow the contact and the consequent "crimping" between core and coating. Such a solution entails the advantage of being more lightweight, even though more complex to carry out. Such features prove particularly advantageous, both by giving greater stability to the end jewel and avoiding the rotation of the rings about the core, which would compromise the aesthetic aspect of the jewel when worn on, as there would not be displayed just one of the four sides anymore.

Subsequently, it is carried out a limbering of the pressed elongated element, consisting in passing it through a plurality of rolls arranged in a sequence, not illustrated in figure, alternatively stationary and swinging ones, to give it the desired flexibility.

The process is repeated twice, rotating the elongated element of 90° about its longitudinal axis. In this step as well, it is fundamental the correct orientation of the hollow coating 30 prior of the entry between the rolls, so that the deformation imposed by the swinging rolls be perfectly aligned to the planes of symmetry 41 and 42.

In other words, the limbering takes place along two directions orthogonal therebetween that, to allow the required flexibility, are substantially aligned with said planes of symmetry 41 , 42 and planes 61 , 62 of maximum flexibility.

Then, the sides of the elongated element thus manufactured may be subjected to a conventional machining of diamond grinding, polishing, satin-finishing, etc., optionally in a way different the one from the other, so as to give, as already explained, different aesthetic aspects on the four sides of the jewel.

At this stage, the end elongated element may be sectioned into a desired number of longitudinal pieces, each one of a size suitable for the manufacturing of a desired jewel or portion thereof.

Then, on some of these pieces there may be carried out all the machining required by the specific intended use thereof.

Subsequently, and referring to figure 14, there may be provided the application of a fastening device 70.

This element has it also particular relevance, since known-art fastening devices use a spring catch mechanism 71, in which the opening is commanded by means of a suitable lever 72.

The assembling of such fastening devices is carried out so that the lever be not in contact with the user's body, since, being substantially of a sharp shape, it would cause inconvenience.

However, the jewel according to the present invention should be wearable on indifferently according to each one of the four sides forming it. Therefore, a traditional fastening device would not allow to prevent the lever from contacting the body in all viable configurations.

For this purpose, the fastening device of the jewel according to the present invention is rotatably connected to the elongated element, so that, by changing the displayed side, the lever of the closing element may it also rotate with regard to the elongated element, never coming into contact with the body.

Moreover, an additional advantage of such a constructive solution lies in that such a fastening device makes simpler the steps of closing and opening the jewel as it allows to keep the lever at all times in the position most favorable to be operated. Always according to a preferred embodiment, the fastening device is made by means of a pin 73 fixed to the elongated element and having a widened portion 74, onto which it is rotatably fixed a spring catch mechanism made essentially according to the known art.

Moreover, it will be understood that the present invention is susceptible of several embodiments and variants alternative to the ones described hereto, some of which are briefly illustrated hereinafter with reference to the sole aspects differentiating them from the embodiments considered hereto.

Referring to figure 12, a variant embodiment immediately evident to a person skilled

in the art consists in obtaining the coating 30 by substantially helically winding an elongated body 80 like, e.g., a flat strip or a wire, in particular directly onto the core 60.

The elongated body 80 will be conveniently prepared and sized, prior of the winding up thereof onto the core 60. Moreover, advantageously there can be carried out also a sizing of the core, so that the elongated body, once wound up thereabout, be evenly distributed, avoiding the presence of steps or grooves onto the surface of the core.

In addition, during the winding up, the elongated body is conveniently kept tensioned as much as possible and moreover oriented in the same direction of the side of the core that each time is being coated. Thus, the coating thus manufactured follows the quadrangular shape of the section as faithfully as possible.

Essentially, the section actually obtained is a square with blunt vertexes, which, though less accurate than that made with the preceding variant, is anyhow sufficient to proceed with the subsequent processing steps. Referring to figure 13, subsequently it is carried out a pressing of the coating so as to obtain a perfectly quadrangular section. During this step, the coating 30 and the core 60 can be correctly oriented by exploiting the shape given to the four sides during the winding up of the elongated body 80. In this case as well, such a correct alignment allows to achieve the desired wearing option features. Then, the limbering is carried out identically to what has been illustrated for the preceding case.

Then, it is performed the machining of the sides and/or a galvanic coloring thereof, allowing to obtain sides of different color, though using starting material of a single color. Finally, fastening device is applied, analogously to the preceding case.

This variant of the method according to the present invention entails the advantage of a higher production rate; yet the recourse to galvanic coloring may lead, over time, to a fading or peeling of the thin electroplated layer, thereby prejudicing the jewel aesthetics. The present invention was hereto described with reference to preferred embodiments thereof. It is understood that there may be other embodiments, referable to the same inventive kernel, all falling within the protective scope of the appended claims.