Fastening element for extendable jewelry

Description

[0001] The present invention relates to items of jewellery, goldsmithery, silverware, bijouterie, ornaments and the like having the characteristic of being provided with lateral extensions or protuberances or recesses, on at least one side of an annular band, as well as items of jewellery, goldsmithery, silverware, bijouterie, ornaments and the like of an extendable type, i.e., in which their dimensions can be modified by applying appropriate tensile or compressive forces.

[0002] Such jewelry items, in order to be manufactured, require operations of very high precision and subdivided into several phases including the realization of a main body, of certain material such as gold or other precious material, enriched in a subsequent production phase by precious stones or the like applied by setting or other combination process.

[0003] In the specific case of extendable items, such items typically consist of an annular band of a predetermined width comprising a plurality of modular elements of elongated shape. At least one of said modular elements is connected to at least three further modular elements by at least three connection points. The modular elements are mutually articulated around each connection point in such a way that the jewelry item is adjustable between a contracted condition and an extended condition.

[0004] Jewelry items of this type are, for example, described in DE9100430, EP1911366 or US9486041 documents.

[0005] In changing from a closed (or contracted) condition to an open (or extended) condition, the dimensions of the item change, thus allowing its shape to be varied without the addition or removal of parts or components.

[0006] On the other hand, the size adjustment, being mostly entrusted to links that articulate with each other, is not stable, but depends on the moderate force exerted on the pins that allow the links to rotate reciprocally.

[0007] This causes an inconvenience when setting stones during the assembly phase of the item itself. Take, for example, a ring which, if its diameter is not firmly fixed once the desired size has been reached, can easily slip off the tool generally used as a support during processing; this inconvenience also occurs in the case of no extendable items, since the high precision required by the setting operations requires that the main body of the item be absolutely stationary, and therefore even the slightest clearance with respect to the support element can compromise the result of the item.

[0008] CN210588922 U discloses a positioning clamp used for processing bracelets. The fixing element of said document comprise teeth that are suitable to engage removably between contiguous modular elements or to lateral elements associated therewith of a jewelry item so as to prevent the articulation of said modular elements and, therefore, the extension of the jewerly item.

[0009] The aim of the present invention is therefore to realise a fixing device for extendable jewelry items which can lock the dimensions of said items once they have reached the desired extension in order to allow for easy processing.

[0010] The invention achieves the aim with a processing head according to claim 1.

[0011] The teeth of the fixing element, which typically have a truncated cone shape with a profile that follows the profile of the spaces between modular elements or between lateral elements associated with them, allow the dimensions of the item to be locked to a certain size so as to allow it to be easily machined.

[0012] Since the links of the jewelry item tend to articulate and thus expand even minimally, in an embodiment it is envisaged that the teeth of the fixing element protrude axially from the fixing element so as to create a groove capable of receiving links or additional cantilevered elements provided in the jewelry item. In this way, it's possible to fix the maximum expansion of the item which is achieved when the links or additional elements are in contact with the bottom of the groove. The additional links can then be removed at the end of the work in order not to affect the aesthetics of the jewelry item.

[0013] The invention thus relates to a head for processing extendable jewelry items, in particular for setting stones on said items. The head has the characteristic of comprising a pair of said fixing elements arranged to turn the teeth in opposite directions so as to be arranged on opposite sides of an extendable jewelry item to stably compress the jewelry item.

[0014] If the jewelry item has an annular shape, such as a ring or a bracelet, each fixing element in the pair has a corresponding annular shape with teeth oriented in the axial direction, i.e. in the direction of fit of the annular jewel so as to engage with the ends of the modular elements, or associated lateral elements, arranged on one side of the jewel. According to one variant, the teeth of the fixing elements are such that they form a pair of circular crowns arranged around the opposite ends of the jewel.

[0015] In one embodiment, the head comprises a cylindrical support for the jewel to be retained of such a diameter that the jewel is in contact with the cylindrical support regardless of the diameter of the ring and the type, regardless of whether the ring is of the extendable type or of the fixed size / diameter, the fixing elements are mounted or mountable coaxially on said cylindrical support so as to be arranged at opposite ends of the jewel and with teeth facing the jewel.

[0016] In one embodiment, the cylindrical support has a longitudinal hole to allow it to rotate around a shaft or pin.

[0017] The cylindrical support, shaft or pin advantageously has at least one protruding end for rotatably coupling the head to a suspension or spindle of a tool, for example a numerical control machine.

[0018] According to an embodiment as claimed in claim 9, the suspension comprises a head as above described, a handle and a pair of U-shaped arms branching off from the Y shape-like handle. The arms have perforated ends for engaging the shaft or pin. This makes for a very simple, portable, and easy-to-use manual fixing head support.

[0019] The cylindrical support can advantageously have locking elements to cooperate with complementary locking elements on one or both suspension arms to prevent rotation of the cylindrical support.

[0020] In particular, in one embodiment the blocking elements of the cylindrical support comprise protuberances alternating with recesses arranged circularly on at least one side of the support, the locking elements of the suspension comprising at least one corresponding recess or projection so as to realise a shape coupling.

[0021] The fixing elements also have on the side opposite the side housing the teeth, corresponding protuberances alternating with circularly arranged recesses which overlap the protuberances and recesses of the support when the fixing elements are mounted on the support.

[0022] The invention also relates to a method for setting stones on an annular shaped jewelry item using fixing elements according to the invention.

[0023] Further features and refinements are the subject of the dependent claims.

[0024] The features of the invention and the advantages derived therefrom will become clearer from the following detailed description in the attached figures, wherein: Fig. 1 shows an example of an extendable jewelry or bijouterie item with a linear extension. Fig. 2 shows further modular elements that can be used to make an extendable jewel. Figs. 3 and 4 show a fixing head, in the open and closed position respectively, of an annular shaped jewelry item according to an embodiment of the invention. Fig. 5 shows further views of the head of Fig. 4. Fig. 6 shows further views of the head of Fig. 4. Figs. 7 and 8 show components of a fixing head of an annular shaped jewelry item according to another embodiment of the invention. Fig. 9 shows a manual machining support for a fixing head according to the invention.

[0025] The processing head according to the present invention is specifically designed for machining jewellery or bijouterie items of the extendable type, i.e. capable of changing their dimensions by applying appropriate tensile or compressive forces.

[0026] Fig. 1 shows an example of it. The jewelry item 1 comprises a plurality of modular elements 2 wherein at least one of said modular elements 2 comprises at least three connection points 3a, 3b, 3c for connection to three further modular elements 2a, 2b, 2c.

[0027] The combination of the above features allows the modular elements 2 to vary their mutual position by switching from a contracted condition in which, in the case of circular shaped items, such as by way of example but not limited to a ring, bracelet or strap, the diameter is minimum, to an extended condition in which the diameter is maximum. The item may be produced in a flat or curved configuration, and be used for example as a pendant, charm, key ring or earring.

[0028] The transition from the contracted to the extended condition and vice versa can be modulated, so that item 1 can acquire all intermediate positions between these two extreme positions and remain in intermediate positions, due to the specific configuration of the robustness of the structure.

[0029] Modular element 2 comprises three substantially circular portions, coinciding with connection points 3a, 3b and 3c, which are connected to each other by two straight intermediate portions to form an elongated element. The intermediate portions may also be curvilinear.

[0030] The jewelry item 1 therefore consists of an annular band of a predetermined width comprising said modular elements 2, which are elongated in shape and are articulated with each other around each connection point 3a, 3b, 3c. The composition is shown in Fig. 1 with a linear development, but it is envisaged, and preferred, that the ends of the composition 1 are joined so as to form a circle structure such as a ring or a bracelet.

[0031] Jewelry objects of this type are, for example, described in DE9100430, EP1911366 or US9486041.

[0032] There may be more complex configurations of which the contraction and expansion movement occurs by oscillation of a certain number of first and second arms, which are hinged to a central axis of hinging and also hinged around two lateral axes of hinging parallel to said central axis in such a way that each first arm is hinged to other three exemplary second arms.

[0033] Hinging takes place by means of connecting elements realised in the form of pins which are housed in their respective housings and in which each pin engages a first and a second arm and the repetition of this hinging gives rise, for example, to the ring shown in the following figures.

[0034] Whichever configuration is adopted, the extendable jewelry items of interest in the present invention are those which generally comprise a plurality of modular elements of elongated shape, such as those shown in Fig. 2, each of which is connected to at least three further modular elements by at least three points of connection so that they can be articulated to each other in a link-like manner so that the jewelry items are adjustable between a contracted condition and an extended condition.

[0035] Modular elements typically have housings for setting precious or bijouterie stones, for example in correspondence of the points of articulations.

[0036] The operation of setting the stones, which can be carried out manually or automatically, e.g. using numerical controlled machines, is very delicate and requires that the elements be held stably in the mounting position. The processing head according to the present invention is designed to facilitate such stones-setting operation, whether manual or automatic. Let us now consider some non-limiting embodiments with reference to Figs. 3 to 9.

[0037] Fig. 3 shows a ring 10 consisting of three rows of claws or bezels (i.e. the support on which the precious stones are set) arranged in correspondence with the points of reciprocal articulation of the modular elements comprising the ring. In this case, the modular elements forming the ring are links of the three-hole type 4a interspersed with a certain regularity by five-hole elements 4b.

[0038] As we will see later, the presence of additional holes allows to guarantee a more stable fixing of the ring, but obviously represents an entirely optional feature since the processing head of the present invention can also act on jewelry items with modular elements with only three holes (4a) as well as with any number of holes such as, for example, the others shown in Fig. 2.

[0039] The ring 10 shown in Fig. 3 is mounted on a cylindrical support 5 having a diameter such as to guarantee a certain extension of the ring 10. The cylindrical support 5 has a longitudinal hole 9 to allow it to rotate around a shaft or pin (not shown in the figures). The cylindrical support 5, the shaft or the pin have at least one protruding end to couple in a rotating manner the head to a suspension or a spindle of a numerical controlled machine.

[0040] There are two circular crowns 6, 6' with a truncated cone shape ending in a toothing 7, 7'. Each crown 6, 6', which represents a ring fixing element according to the invention, is arranged on the cylindrical support 5 on opposite sides of the ring 10 to stably compress it when the crowns are brought closer as shown in Fig. 4. Crowns 6, 6' and cylindrical support 5 form a processing head according to the invention.

[0041] The teeth 7, 7' of the two crowns 6, 6' are arranged axially i.e. in the direction of fit of the ring 10 and are directed in opposite directions so as to engage between contiguous modular elements (4a, 4b, 4c, 4d, 4e as in Fig. 2, depending on the constructional choice of the elements composing the jewel), or by lateral elements associated with them, so as to prevent the articulation of the modular elements and, therefore, the extension of the ring 10.

[0042] As can be appreciated from the views shown in Fig. 5 and 6, the teeth 7, 7' of each crown 6, 6' protrude axially so as to create a groove 8 capable of receiving five-hole links 4b or additional cantilevered elements provided in the ring 10. In this way it is possible to fix the position of maximum expansion required by the operator during machining operations, which is obtained when the links or additional elements are in contact with the bottom of the groove.

[0043] In the specific case shown in the figures, it is the fourth link 4b which is inserted into the groove 8. If no links or cantilevered elements are present the groove 8 remains disengaged as shown in the left-hand part of detail B shown in Fig. 5.

[0044] The presence of additional links 4b engaging in the groove 8 ensures a stable fixing in the ring 10. The teeth 7, 7' are in fact not sufficient in themselves to prevent even the slightest articulation of ring 10 which could create inconveniences especially in the case of automatic stones-setting operations. In manual operations, small changes in the shape of the ring are more tolerated, so the presence of cantilevered links can be obviated, even considering that these additional links must in any case be removed at the end of the working process with a consequent increase in production time.

[0045] Figs. 7 and 8 show components of a locking head according to the invention which are particularly suitable for use in manual processing using a support acting as a suspension such as exemplary shown in Fig. 9.

[0046] The manual machining support shown in this figure comprises a handle 100 onto which a head formed by a pair of U-shaped arms 101 is screwed or bolted so as to form an overall Y shape-like structure. The arms 101 have perforated ends 102 for engaging a pin housed in the longitudinal hole 9 of the cylindrical support 5.

[0047] The cylindrical support 5 has on one end, preferably on both ends, protuberances 51 alternating with recesses 52 arranged circularly in a lacework-like form. The recesses 52 are provided for coupling with a projection 103 present on one or both arms 101 of the machining support so as to prevent rotation of the cylindrical support 5 and, therefore, of the ring mounted thereon until a torque is exerted on the cylindrical support 5 such that the projection 103 can be overcome for engagement with the next recess 52 in a jerky rotational movement.

[0048] In one embodiment, the crowns 6, 6' have on the side opposite to the one housing the teeth 7, corresponding protuberances 61 alternating with circularly arranged recesses 62 which overlap the protuberances 51 and the recesses 52 of the support 5 when the crowns are mounted on the machining support.

[0049] When the processing head is mounted on a spindle of, for example, a numerical controlled machine, the protuberances and recesses of the cylindrical support can be used to make a shape coupling with a corresponding processing head of the machine which is responsible for gradually rotating the support as the stones are set, for example by means of robotic arms.

[0050] For this purpose, the invention also relates to a method for setting stones on an annular shaped jewelry item, such as a bracelet or a ring. The method comprises the following steps: having a processing head according to the invention; having a shaft or spindle of a tool; insert a first fixing element of the processing head on the spindle with teeth facing towards the free end of the spindle; insert the jewelry item on the spindle by acting on the links of said item up to the diameter of the spindle; insert the other fixing element of the processing head on the spindle with the teeth facing the jewelry item so that the fixing elements are arranged on opposite sides of the jewelry item; adjust the position of the fixing elements on the spindle so that the teeth engage on the perimeter part of the jewelry item to stably fix it; set the stones on the housings specially provided on the jewelry item, if necessary by rotating the spindle to expose said housings to the operator or tool performing the work.

[0051] If the jewelry item comprises links or additional lateral cantilevered elements which engage in a groove of the fixing elements when the teeth of said fixing elements engage on the perimeter part of the jewelry item, the method includes the step of removing said links or additional cantilevered elements after completion of processing after releasing the item from the fixing elements.

[0052] The invention is primarily described for use with items of jewellery, goldsmithery, silverware, bijouterie, ornaments and the like having the characteristic of being extendable, i.e., of changing their dimensions by applying appropriate tensile or compressive forces.

[0053] The person skilled in the art can, however, appreciate how the same inventive teachings can also be applied to items of jewellery, goldsmithery, silverware, bijouterie, ornaments and the like, which are not necessarily extendable, but which are however provided with lateral extensions or protuberances or recesses, on at least one side, such as to allow the engagement of the teeth of the fixing element and / or the processing head according to the invention.

[0054] This is particularly advantageous in that it avoids the use of commonly used item-blocking supports, such as teflon dowels, which are unable to guarantee a stable fixing when setting stones.

[0055] The lateral extensions, protuberances or recesses can be added to the item to be then removed when the work is finished, as in the case of the additional cantilevered links that engage in the groove of the fixing elements, or they can be elements that are part of the final item, either naturally present or inserted on purpose, to allow the ring to be squeezed between the circular crowns forming the fixing elements and / or the head according to the invention.

[0056] All without abandoning the informing principle set forth above and hereinafter claimed.

Claims

1. A processing head of extendable jewelry items (10), of the type comprising a plurality of modular elements of elongated shape (2, 4a-4e), at least one of said modular elements being connected to at least three further modular elements by at least three connection points, said modular elements (2, 4a-4e) being mutually articulated around each connection point in such a way that the jewelry item (10) is adjustable between a contracted condition and an extended condition, in particular for setting stones on said jewelry items, comprising a pair of fixing elements (6, 6'), the fixing elements comprising teeth (7, 7') such as to engage removably between said contiguous modular elements (2, 4a-4e) or to lateral elements associated therewith so as to prevent the articulation of said modular elements and, therefore, the extension of the jewelry item (10), each element of the pair being arranged so as to turn the teeth (7, 7') in opposite directions so as to be arranged on opposite sides of an extendable jewelry item (10) to stably compress, when in position, said jewelry item (10).

2. Processing head according to claim 1, wherein the teeth (7, 7') of the fixing elements (6) have a truncated cone shape with a profile following the profile of the spaces between modular elements (2, 4a-4e) or between lateral elements associated therewith.

3. Processing head according to claim 1 or 2, characterised in that it is provided for fixing a ring or a bracelet or in any case a ring-shaped jewel (10) having a diameter varying from a minimum value to a maximum value, wherein each fixing element (6, 6') of the pair has a corresponding annular shape with teeth (7, 7') oriented in the axial direction, i.e., in the direction of engagement of the annular jewel (10) so as to engage on the ends of the modular elements (2, 4a-4e), or of lateral elements associated therewith, arranged on one side of the jewel (10).

4. Processing head according to one of the preceding claims, wherein the teeth (7, 7') of the fixing elements (6, 6') are such as to form a pair of circular crowns arranged around the opposite ends of the annular jewel (10).

5. Processing head according to claim 3 or 4, characterised in that it comprises a cylindrical support (5) for the jewel (10) to be retained of such a diameter that the jewel is in contact with and integral on said support when wound thereon, the fixing elements (6, 6') being coaxially mounted or mountable on said cylindrical support (5) so as to be arranged at the opposite ends of the jewel (10) and with teeth (7) facing the jewel (10).

6. Processing head according to claim 5, wherein the teeth (7, 7') of the fixing elements (6) protrude axially from the fixing elements (6) so as to create a groove (8) suitable for receiving links (4b) or additional cantilevered elements provided in the jewelry item (10) so as to fix the maximum expansion of the item which is obtained when the links (4b) or the additional elements are in contact with the inner walls of the groove (8).

7. Processing head according to claim 5, wherein said cylindrical support (5) has a longitudinal hole (9) to allow rotation thereof around a shaft or pin.

8. Processing head according to claim 5 or 7, wherein the cylindrical support (5) itself or said shaft or said pin have a coupling end in a rotation seat provided in a suspension element and / or in a spindle of a machine tool, optionally of the numerical controlled type.

9. A hand machining support for jewelry items (10) of the type comprising a plurality of elongated modular elements (2, 4a-4e), comprising: - a head according to any one of claims 5 to 8; - a suspension comprising a handle (100) onto which is screwed or bolted an appendage formed by a pair of U-shaped arms (101) so as to form an overall Y shape-like structure, wherein the arms (101) have perforated ends (102) for engaging a pin or a shaft housed in the longitudinal hole (9) of the cylindrical support (59.

10. Support according to claim 9, wherein the cylindrical support (5) has blocking elements (51, 52) capable of cooperating with complementary blocking elements (103) present on one or both of the arms (101) of the suspension to prevent rotation of the cylindrical support (5).

11. Support according to claim 10, wherein the blocking elements (51, 52) of the cylindrical support (5) comprise protuberances (51) alternating with recesses (52) arranged circularly on at least one side of the support (5), the suspension blocking elements comprising at least one corresponding recess or projection (103) so as to achieve a shape coupling preventing rotation of the support (5).

12. Support according to claim 11 wherein the fixing elements (6, 6') have, on the side opposite the side housing the teeth (7, 7'), corresponding protuberances (61) alternating with circularly arranged recesses (62) which overlap the protuberances (51) and the recesses (52) of the support (5) when the fixing elements (6, 6') are mounted on the support (5).

13. Use of a head according to any one or more of the preceding claims 1 to 8 or a support according to any one or more of the preceding claims 9 to 12, with items of jewellery, goldsmithing, silverware, bijouterie, ornaments and the like, also of the non-extendable type, comprising extensions or protuberances or lateral recesses, on at least one side, on which the teeth of the fixing element or elements can engage.

14. A method for setting stones on an jewelry item having an annular shape, such as a bracelet or a ring, characterised in that it comprises the following steps: - having a head according to any one or more of the preceding claims 1 to 8; - having a spindle of a tool; - inserting a fixing element (6) of the pair on the spindle with the teeth (7) pointing towards the free end of the spindle; - inserting the jewelry item on the spindle by acting on the links of said item until the diameter of the spindle is reached; - inserting the other fixing element (6') of the pair on the spindle with the teeth (7') facing the jewelry item so that the fixing elements are on opposite sides of the jewelry item; - adjusting the position of the fixing elements on the spindle so that the teeth engage on the periphery of the jewelry item to stably fix it; - carrying out the operation of setting the stones on specially provided housings on the jewelry item, possibly rotating the spindle to expose said housings to the operator or to the tool performing the operation.

15. A method according to claim 14, wherein the jewelry item comprises links or additional lateral cantilever elements that engage in a groove of the fixing elements when the teeth of said fixing elements engage the perimeter portion of the jewelry item, the method comprising the step of removing said links or additional lateral cantilever elements at the end of the operation after having released the item from the fixing elements.

16. A method according to claim 14 or 15, wherein the jewelry item comprises extensions or lateral protuberances or recesses, on at least one side, the step of adjusting the position of the fixing elements on the spindle comprising, in combination or alternatively, approaching the fixing elements to the item so as to cause the teeth to engage on said extensions or protuberances or lateral recesses to stably fix the jewelry item, even if of the non-extendable type.