Patent Description:
In the field of costume jewellery, jewellery and the like, the known art is full of reference products for a variety of solutions concerning the joints connecting the ends of elements such as necklaces, bracelets, anklets and the like. Such joints have the purpose of mutually fixing the two ends so as to arrange such elements around the wrist, neck or ankles of the end users.

Among the traditional fastening systems of the above-mentioned elements, fasteners are chosen such as to ensure a predetermined strength and a low risk of accidental opening. Among the various types of fasteners, clasps and snap hook closures are among the most preferred. However, such fasteners, in the case of small costume jewellery items, lead to difficulties for the end users in the operation of connecting or disconnecting the two ends of the costume jewellery element. In particular, the small size makes it difficult to manipulate the fastening joints, often causing end users frustration when putting on or taking off a given costume jewellery element.

In the case of necklaces, for example, a user could need the help of a mirror or the assistance of a second person to be able to correctly manipulate the fastening of the costume jewellery element. In the case of bracelets, a user would instead need the assistance of a second person as it is necessary to use both hands to manipulate the fastening. Such disadvantages can also be found in other types of traditional fastenings beyond those mentioned above.

Recently, a number of solutions have emerged in the known art which propose joints for costume jewellery elements and jewellery elements characterised in that the items can be closed/opened with moderate ease. In particular, European patent <CIT> proposes costume jewellery elements characterised by the sequence of a set of interconnected modules, mutually assembled by a snap-fit connection system. A snap-fit connection is understood as a male-female type joint, where the male portion generally comprises an extending or protruding member which is received in a special female seat, and such a male portion is held in the engaged position by means of forces counteracting the release by exploiting friction and/or elastic mechanical interference from the female portion.

Always according to patent <CIT>, each module is characterised by the presence of a pin, having a rounded head mounted on a neck, where the cross-sectional diameter of the head is greater than the cross-sectional diameter of the neck. The pin is connected to the surface of the module and can be axially engaged to an engagement seat inside the body of a second module, capable of receiving the pin. The engagement of the pin inside the seat is maintained stable because the engagement seat has an inlet segment with a respective inlet hole, the diameters of which are smaller with respect to the cross-sectional diameter of the head but have geometries such as to make them flexibly radially expandable during the insertion of the head.

Once the head passes beyond the inlet segment and is received inside the engagement seat, the hole of the inlet segment returns to the starting value around the neck of the pin. The elastic force exerted on the inlet segment is calibrated so as to prevent the rounded head of the pin from unintentionally exiting from the engagement seat.

Each module comprises a pin and an engagement seat, respectively, where the engagement seat is arranged diametrically opposite the pin to the module body. Such an arrangement allows a concatenation of modules to obtain closed chains of different sizes, which can be worn as bracelets, necklaces, anklets, etc..

The main advantage of such a solution would be in the ease with which an end user can engage two modules, a manual compression between two modules being sufficient, in particular so that the pin of a first module engages inside the engagement seat of a second module. Similarly, a traction of sufficient intensity is sufficient for two modules to disconnect.

Potentially, a user has the possibility of opening and closing the chain at any connecting point between the modules, having a costume jewellery element which is easy to put on, easy to take off and easy to modify due to the interchangeability of the modules forming the chain.

For example, a connector configured to connect two ends of a necklace is known from <CIT>: such a connector comprises a female element fixed to one end of the necklace and a male element fixed to the other end of the necklace. An annular spacer can be interposed between the male element and the female element for decorative purposes or for adjusting the gap, and moreover a convex portion is formed on one side of the male element. An engagement groove is formed in the centre of the convex portion.

Also known from <CIT> is a chain connector comprising a pair of connecting elements, each of which has a hollow body: a first connecting element comprises a male connecting element with an enlarged head and a convex segment extending axially from a concave wall, while a second connecting element comprises a cavity intended to receive the head and a spring assembly arranged at the inlet of the cavity, shaped specularly concave to the concave wall, in which such a spring assembly is configured to close around the convex segment.

Disadvantageously, the known solutions presented above have several negative aspects.

In particular, a first disadvantage results from the fact that the materials chosen to establish said modules must have predetermined mechanical features, in order for the structural integrity of the module chain to be maintained.

In particular, in order to ensure the structural integrity of the module chain, the modules must be sufficiently strongly coupled to avoid accidental openings along the chain. Such a risk is conditioned by the presence of a multiplicity of connections between the modules, significantly increasing the probability of accidental opening. For such a reason, the solution favours a high ratio of the size of the rounded head diameter with respect to the diameter of the hole of the housing seat, so as to reinforce the seal of the various couplings and prevent the accidental opening thereof. However, such a choice can make the operation of inserting the head in the housing rather difficult, requiring a high manual force for insertion and resulting in an unpleasant effect for the end user.

Additionally, the solution appears to be formed such that if the pin breaks, the entire module must be replaced. For such a reason, the present solution has the module body preferably made of metallic materials, so as to increase the mechanical strength and minimise the risk of breakage. Other materials, such as hard plastic, can also be used but have less mechanical strength. Hard but fragile materials, such as ceramics or other minerals, are instead totally unsuitable.

It is therefore a technical task of the present invention to provide a reversible joint for a costume jewellery element or jewellery element or the like which is/are capable of overcoming the drawbacks in the known art of both the traditional and alternative systems, such as the system cited in patent <CIT>.

An object of the present invention is therefore to provide a reversible joint for a costume jewellery element, jewellery element or the like, adapted to connect by means of an interlocking mechanism respectively a first and a second end of a body of a costume jewellery element such as to ensure an easy opening and closing by the end user, in particular in the case of small costume jewellery elements.

A further object of the present invention is to provide a reversible joint for a costume jewellery element, jewellery element or the like characterised by the compatibility with bodies of costume jewellery, jewellery or the like having shapes and structures traditionally used in the field of costume jewellery, jewellery or the like.

A further object of the present invention is to provide a reversible joint for a costume jewellery element, jewellery element or the like characterised by the modular constitution of the joint itself, in which the various components can be easily and reversibly connected to each other, facilitating both the assembly and repair of the joint, as well as the possibility of using different types of functionally suitable materials for each modular element of the joint.

The object of the present invention further includes a simple and effective method for assembling a reversible joint for a costume jewellery element, both with regard to assembly and with regard to the replacement of the respective components of such a joint.

The specified technical task and the specified objects are substantially achieved by a reversible joint for a costume jewellery element, jewellery element or the like comprising the technical features set forth in one or more of the appended claims.

In particular, a reversible joint is described for fastening costume jewellery elements, jewellery elements or the like, in which the joint is adapted to respectively connect a first and a second end portion of a costume jewellery element or jewellery element or the like by means of a reversible interlocking mechanism, in particular, by means of the insertion of a pin, included in a first section of the joint, inside a bearing, arranged inside an engagement seat included in a second section of the joint.

Further features and advantages of the present invention will become clearer from the indicative, and therefore non-limiting, description of a preferred but non-exclusive form of a reversible joint for costume jewellery elements, jewellery elements or the like.

Such description will be set forth herein below with reference to the accompanying drawings, provided for merely indicative and therefore non-limiting purposes, wherein:.

With reference to the appended drawings, a reversible joint for costume jewellery elements or jewellery elements in accordance with the present invention, hereinafter referred to simply as "costume jewellery element", has been designated <NUM>.

The joint <NUM> is adapted to respectively connect a first end portion and a second end portion of a costume jewellery element (not depicted as not the subject matter of the present invention).

The joint <NUM> comprises a first section <NUM> and a second section <NUM> which are reversibly connectable by means of an interlocking mechanism, i.e., each having respectively at least one male-female mutual coupling member, in which the female member reversibly receives and retains the male member therein by friction and/or elastic mechanical interference.

The appended drawings illustrate a preferred embodiment in which each among the first section <NUM> and the second section <NUM> have only one mutual coupling member, respectively; however, different embodiments can provide for several such mutual coupling members thereof.

In the present embodiment illustrated in the appended drawings, the joint <NUM> has a substantially cylindrical body, but in alternative embodiments it can also provide different geometries.

The first section <NUM> has at a longitudinal end a male coupling member in the form of a connecting pin <NUM>. The connecting pin <NUM> comprises a main body <NUM>, a rounded and/or longitudinally concave head <NUM> and a convex segment <NUM>.

In particular, the convex segment <NUM> interposes itself as a connection between the rounded head <NUM> and the main body <NUM>.

Overall, the coupling pin extends according to an elongated geometry, preferably axial-symmetric.

The rounded head <NUM> has a rounded concave geometry, sized so as to have a cross-sectional diameter which is always larger with respect to the minimum cross-sectional diameter of the convex segment <NUM>. As the head <NUM> is arranged adjacent to the convex segment <NUM>, the overall geometry of the transverse shape results in an initial bulge having an inflection and naturally opening into a narrowing, coinciding with the convex segment <NUM> itself, later widening again to merge into the main body <NUM> of the pin <NUM>.

In the present preferred but not exclusive embodiment, the pin <NUM> is arranged axially inside said first section <NUM>. In particular, the main body <NUM> is entirely received inside the first section <NUM>, while the convex segment <NUM> and the rounded head <NUM> are instead arranged entirely externally.

The first section <NUM> can consist of a single body or a plurality of components.

According to the embodiment illustrated in the present drawings, the first section <NUM> consists of a first subsection <NUM> and a second subsection <NUM>.

The two subsections <NUM> and <NUM> are arranged adjoining and receiving the main body <NUM> of the pin <NUM>. In particular, the main body <NUM> has a fastening <NUM>, preferably threaded or interlocking at a corresponding connecting zone <NUM> of the first subsection <NUM>, allowing a firm connection of the pin to the first section <NUM>. Such a fastening <NUM> is situated at the end of the main body <NUM> which is distal with respect to the convex segment <NUM> and the head <NUM>. The second subsection <NUM> is wrapped around the main body <NUM>. The second subsection <NUM> longitudinally contacts the first subsection <NUM> at one end and allows the exit of the head <NUM> and the convex segment <NUM> at the opposite end.

With reference to <FIG>, according to the present non-exclusive embodiment, the pin <NUM> has a stepped segment <NUM> on the portion of the main body <NUM> proximal to the convex segment <NUM>. The stepped segment <NUM> extends projecting transversely with respect to the remaining portion of the main body <NUM>. The stepped segment <NUM> engages, compatibly in shape, with a corresponding annular section <NUM> inside the second subsection <NUM>, keeping the second subsection <NUM> in position and adhering against the first subsection <NUM>.

The second section <NUM> has a substantially cylindrical body having a female member comprising an engagement seat <NUM> receiving said pin <NUM> of the first section <NUM>.

The engagement seat <NUM> is arranged inside the second section <NUM>. In particular, the second section <NUM> comprises an opening <NUM> at a first longitudinal end which puts the engagement seat <NUM> in communication with the outside.

In the embodiment illustrated in the present drawings, the engagement seat <NUM> and the corresponding opening hole <NUM> are arranged axially with respect to said second section <NUM> such that they are capable of axially receiving the pin <NUM> and permitting an axial connection between said first section <NUM> and the second section <NUM> of the joint <NUM>.

The housing seat <NUM> comprises an elastic bearing <NUM> therein, which is reversibly inserted. Preferably, the shape of the bearing <NUM> is cylindrical or annular or tubular around an axis "A".

The geometry of the engagement seat <NUM> substantially follows that of the bearing <NUM>, wrapping entirely therearound except for the hole <NUM>, retaining it therein and preventing it from accidentally exiting.

The bearing <NUM> has an inner cavity <NUM>, preferably extending around the axis "A", and in which said pin <NUM> can be reversibly inserted axially.

The cavity <NUM> is preferably pass-through with respect to the bearing <NUM>, comprising an inlet portion <NUM> and an outlet portion <NUM>. The inlet portion <NUM> is aligned with the opening <NUM> of the engagement seat <NUM>. The pin <NUM> is capable of being reversibly inserted internally along the axis "A" and along the entire length of the inner cavity <NUM> of the bearing <NUM>, preferably emerging beyond the outlet portion <NUM>. The inserted pin <NUM> is held in position by elastic mechanical interference with the cavity <NUM> of the bearing <NUM>. In particular, at least the outlet portion <NUM> of the cavity <NUM> is capable of elastically deforming, allowing the bearing <NUM> to wrap around the head <NUM> and the intermediate segment <NUM> of the pin <NUM>.

The diameter of the outlet portion <NUM> is smaller than the diameter of the inlet portion <NUM>.

The retention in position of the pin <NUM> in the engagement seat <NUM> is ensured on the one hand by the choice of a specific range of values both of the dimensional ratio between the cross-sectional diameter of the head <NUM> and the cross-sectional diameter of the inner cavity <NUM> of the bearing <NUM> and of the dimensional ratio between the cross-sectional diameter of the convex segment <NUM>, and in particular the minimum cross section of the convex segment <NUM>, and the diameter of the inner cavity <NUM> of the bearing <NUM>.

In particular, the dimensional ratio of the cross-sectional diameter of the head <NUM> to the cross-sectional diameter of a minimum section of the inner cavity <NUM> of the bearing <NUM> is comprised between <NUM> and <NUM> with a tolerance of <NUM>%. Instead, the dimensional ratio between the cross-sectional diameter of the minimum section of the convex segment <NUM> and the cross-sectional diameter of the minimum section of the inner cavity <NUM> is comprised between <NUM> and <NUM> with a tolerance of <NUM>%.

Such ratios define limiting ranges derived from the consideration of the possible extensions of the overall geometric shape of the head <NUM> and convex segment <NUM> in relation to the dimensions of the inner cavity <NUM>, advantageously allowing for a good compromise between the necessary insertion/disconnection force and the stability of the joint <NUM> in the event of accidental openings.

The inner cavity <NUM> can be irregularly shaped, but preferably, it has a tapered shape. Tapered is intended as a geometric extension where the inner cavity <NUM> is progressively reduced in section. Such a reduction can be linear, curvilinear, broken or other.

Consequently, the inner cavity <NUM> has the inlet portion <NUM> characterised by a larger diameter with respect to the diameter of the outlet portion <NUM>.

Since the diameter of the outlet portion <NUM> is smaller than the inlet portion <NUM>, the insertion of the head <NUM> causes an elastic deformation of the inner cavity <NUM>, in particular of at least said outlet portion <NUM>, at least during the crossing of the outlet portion <NUM> by the head <NUM>.

The engagement between the bearing <NUM> and the pin <NUM> results from the equilibrium position achieved by the arrangement of the head <NUM> and the convex segment <NUM> inside the inner cavity <NUM>. In particular, the engagement position is kept stable due to the geometry of the convex segment <NUM> where the bearing <NUM> wraps around, mechanically interfering with the head <NUM> and preventing the head <NUM> from freeing itself.

The convex segment <NUM> can have a more or less marked longitudinal convexity, such that it accentuates the overall longitudinal concavity of the head <NUM>. Additionally, the tapered shape and the outlet portion <NUM> with a smaller diameter with respect to the diameter of the inlet portion <NUM> allow an easier insertion of the pin <NUM> inside the bearing <NUM> with respect to the disengagement, advantageously differentiating the force required for insertion and disengagement.

The bearing <NUM> has a crooked slit <NUM>, extending between the inlet portion <NUM> and the outlet portion <NUM> of the inner cavity <NUM>, which facilitates the elastic deformation of the bearing <NUM> and the wrapping of the bearing <NUM> around the head <NUM> and the intermediate segment <NUM>. In particular, such a slit <NUM> preferably results in a continuous interruption along the bearing <NUM>, allowing the bearing <NUM> to progressively adapt and deform, when the pin <NUM> is sliding inside the cavity <NUM>, and facilitating the wrapping of the bearing around the head <NUM> and the intermediate segment <NUM>.

A further important factor of the present invention is the set of chosen materials forming the various components of the joint, in particular the head <NUM> and the bearing <NUM>.

In particular, for the head <NUM>, materials chosen from metal and rigid plastic were preferred, i.e., materials characterised by stiffness and high mechanical strength under static and fatigue conditions.

Stiffness refers to materials characterised by resistance to an external stress, and in particular the ability of a solid specimen to resist an external bending or torsion stress.

Static mechanical strength refers to the ability of a specimen to resist static mechanical stress.

Mechanical fatigue strength is defined as the maximum stress which can be withstood by a specimen for a defined number of cycles without breaking the specimen.

In other words, the pin <NUM> is formed so that it has a certain ability to withstand stress without breaking both in the engaged position and during insertion and disengagement inside the bearing <NUM>.

For the bearing <NUM>, samples made of materials chosen from resins and plastics were preferred, with a particular preference for acetyl or POM C resins, i.e., materials characterised by stiffness, resilience and high mechanical fatigue strength.

Resilience refers to the elastic resistance of a specimen to mechanical stress, or more precisely, the ability to absorb energy and release it elastically while maintaining the geometry thereof.

In other words, the bearing <NUM> is formed so that it is elastic enough to adapt to the shapes and dimensions of the head <NUM> and convex segment <NUM>, but at the same time rigid enough to create enough mechanical interference to prevent the accidental exit of the pin <NUM>.

Additionally, the bearing <NUM> must have a predetermined ability to withstand numerous engagement cycles with the aforementioned pin <NUM>.

Advantageously, the combination of the above-mentioned features allows to achieve a resistance to opening which is sufficient to prevent accidental opening but at the same time does not require a great deal of manual effort on the part of end users to perform both insertion and disengagement.

The joint <NUM> is modularly constructed so that each component can be easily and reversibly assembled and possibly replaced.

The pin <NUM> is reversibly fixed or fixable to the first section <NUM> of the joint <NUM>. Such a feature allows a pin of a different material with respect to the material chosen for the joint <NUM> to be used.

Advantageously, a pin <NUM> consisting of a first material which is more resistant to mechanical stress can be coupled with the first section <NUM> of the joint <NUM>, made of a second material which is different with respect to the material used for the pin <NUM>.

In particular, in the event of breakage due to excessive mechanical stress, the pin <NUM> can be replaced without having to replace the entire first section <NUM> of the joint <NUM>.

Similarly, the bearing <NUM> is also reversibly fixed or fixable to the second section <NUM> of the joint <NUM>. Consequently, the bearing <NUM> can be made of a different material with respect to the second section <NUM> of the joint <NUM> and suitably replaceable if necessary without necessarily having to replace the entire section <NUM> of the joint <NUM>.

The first section <NUM> and the second section <NUM> of the joint <NUM> can be provided consisting of materials with low mechanical performance but more aesthetically pleasing. It can be provided to exploit not only metals and hard plastics but also less mechanically resistant materials such as ceramics, minerals or the like. The first section <NUM> and the second section <NUM> must only be able to hold the pin <NUM> and the bearing <NUM> firmly in place, respectively.

The first section <NUM> and the second section <NUM> of the reversible joint <NUM> have a first seat <NUM> and a second seat <NUM>, respectively, adapted to receive and hold the respective end portions of the costume jewellery element. The first seat <NUM> is arranged at the end of the first section <NUM> which is distal with respect to the end comprising the head <NUM>. The second seat <NUM> is arranged on the end which is distal with respect to the end comprising the opening <NUM> for the engagement seat <NUM>.

In particular, the first seat <NUM> and the second seat <NUM> correspondingly have a first retaining portion <NUM> and a second retaining portion <NUM> intended to engage with the costume jewellery element in various manners, such as, but not limited to, by means of threaded coupling or mechanical interference fit. The costume jewellery element to which the joint <NUM> connects can advantageously feature shapes, structures and designs traditionally used in the field such as chain bodies, rope bodies, wire bodies, leather bodies and others.

The reversible joint <NUM> can have at least one additional hooking mechanism, placed either on the first section <NUM> or on the second section <NUM> or on both, with the purpose of further reinforcing the fastening of the joint to prevent accidental opening.

Preferably, such an additional hooking mechanism comprises an additional hooking element <NUM> in the form of a tab made in a single piece and arranged longitudinally as an extension to one between the first section <NUM> and the second section <NUM>. Such an additional hooking element <NUM> can be coupled to a hooking seat <NUM> arranged on the corresponding opposite section.

In the embodiment illustrated in the present illustrations, it has been chosen to depict such an additional hooking element <NUM> arranged on the second end <NUM>. The hooking seat <NUM> is instead arranged on the first end <NUM>. In particular, such a hooking seat <NUM> is arranged on the surface of the section which is opposite and counter-shaped to the geometry of the additional hooking element <NUM>. When coupling the first section <NUM> with the second section <NUM> of the joint <NUM>, the additional hooking element <NUM> is inserted, preferably transversely, in the coupling seat <NUM>.

The additional hooking element <NUM> and the hooking seat <NUM> exert mutual retention by mechanical interference of the corresponding contact surfaces and/or by means of the choice of using specific geometries which hinder decoupling.

The hooking element <NUM> and the hooking seat <NUM> can comprise a further retaining mechanism not illustrated in the present drawings.

Given a first contact surface <NUM> and a second contact surface <NUM>, which correspondingly belong to the hooking seat <NUM> and the additional hooking element <NUM>, the first contact surface <NUM> has a plurality of reliefs while the second contact surface <NUM> in turn has a plurality of grooves compatible with the aforementioned reliefs. During the coupling of the first section <NUM> with the second section <NUM> of the joint <NUM>, the reliefs are engaged or reversibly engaged with the grooves supporting the retention and maintenance of the coupling position between the hooking seat <NUM> and the additional hooking element <NUM>, and thus between the first section <NUM> and second section <NUM>.

An assembly method in accordance with the present invention concerning a reversible joint <NUM> for a costume jewellery element or the like is further presented.

Such a method comprises, the arrangement of a costume jewellery element and the arrangement of a joint <NUM>, having a first section <NUM> and a second section <NUM>, comprising a pin <NUM> and an elastic bearing <NUM> respectively, and made in accordance with the present description.

Claim 1:
Reversible joint (<NUM>) for fastening costume jewellery elements, jewellery elements or the like comprising:
- a first section (<NUM>), connected or connectable to a first end portion of a costume jewellery element, said first section (<NUM>) comprising a connecting pin (<NUM>) having a main body (<NUM>), a rounded and/or longitudinally concave head (<NUM>) and a convex segment (<NUM>) defined between said head (<NUM>) and said main body (<NUM>), said head (<NUM>) having a cross-sectional diameter larger than a minimum cross-sectional diameter of said convex segment (<NUM>); and
- a second section (<NUM>), connected or connectable to a second end portion of a costume jewellery element, said second section (<NUM>) comprising an engagement seat (<NUM>) adapted to house said connecting pin (<NUM>) and comprising an elastic bearing <NUM> having an inner pass-through cavity (<NUM>);
wherein said first section (<NUM>) and said second section (<NUM>) may be reversibly connected by introducing said pin (<NUM>) into said bearing (<NUM>), said pin (<NUM>) being held in position within said bearing (<NUM>) by mechanical interference;
characterised in that:
- said cross-sectional diameter of said head (<NUM>) and a cross-sectional diameter of a minimum section of said pass-through cavity (<NUM>) have a dimensional ratio ranging from <NUM> to <NUM> with a tolerance of <NUM>%;
- said cross-sectional diameter of a minimum section of said convex segment (<NUM>) and the cross-sectional diameter of a minimum section of said inner pass-through cavity (<NUM>) have a dimension ratio ranging from <NUM> to <NUM> with a tolerance of <NUM>%; and
- said inner pass-through cavity (<NUM>) has an inlet portion (<NUM>) and an outlet portion (<NUM>), wherein a diameter of said outlet portion (<NUM>) is smaller than a diameter of said inlet portion (<NUM>), and wherein while introducing said head (<NUM>) within said bearing (<NUM>), at least said outlet portion (<NUM>) is elastically deformable.