DESCRIPTION

FIELD OF THE INVENTION

The present invention concerns a system for constraining lenses in an eyeglass frame, as well as an eyeglass frame specially designed to best exploit such a system.

STATE OF THE ART

As known, in the field of eyeglass frames, numerous systems for holding in lenses in the frame itself have been proposed.

Most of the time the joint of the metallic profile that hold the lens perimetrically is used, transforming it into a clamp, welding two small tubes, one for each end, one perforated and the other threaded, the whole thing being joined together by means of a screw.

Other systems foresee a half-frame that engages about half of the perimeter of the lens, whereas the other half is engaged by an extensible wire (generally made from Nylon ^® ), rigidly fixed at two extreme points of the half- frame.

These systems, although they work and have been tested, do have problems linked to the complexity of the machining to be carried out that, in the first case, concerns the substantial number of pieces used and of microwelds to be made, whereas in the second case it concerns the need to make micro-holes in which to fasten the Nylon ^® wire; these problems increase the costs and lengthen the manufacturing time.

Another example of the prior art is found in US-A-006015212, where there is, however, a mixed structure, assembled with various pieces that determine instability and complexity of assembly; moreover, since the structure is open, the lenses are firstly locked and then angularly adjusted, for correct optical centring, with obvious problems.

Another example worth noting is found in the two inventions described in documents EP 1962126A2 and GB 2178864 A, in which there are two conceptually similar structures identified in the locking system of the lenses through a single central fastener, arranged near to the bridge of the frame; such a system, even if it works perfectly well to allow the correct centring of the lenses before locking, thanks to the closed structure of the frame, does however force the lenses to be locked simultaneously, forcing the worker to calibrate perfectly, otherwise the frame will be poorly assembled, with the risk of losing the lenses, if they are slightly too small.

We also quote document EP-A-0838710.

The purpose of the present invention is to avoid the aforementioned drawbacks, offering a system that is cost-effective to product, without mechanical machining such as welding, gluing, perforation, screwing; all of this is obtained by sheet moulding, through laser cutting, or else through chemical milling. The purpose is also to offer a system that is simple to mount and dismount, both in the factory assembly step and in the optician's shop, during the mounting of the lenses of the end user and, not to be underestimated, with the possibility of mounting a single lens at a time, thanks to the double fastener, one for each lens.

BRIEF DESCRIPTION OF THE INVENTION

Such purposes are accomplished through the characteristics quoted in the attached independent claim, whereas the dependent claims describe preferred characteristics in the present invention. In particular, according to the invention, a system for constraining the lenses is provided, which comprises a nosepad-carrying fastener that, being hinged at a point of the metallic frame at the lower bridge, rotates and locks another portion of the frame itself, opposite the first, clamping around the lens contained in it

(the shape of the pad-carrying fastener is purely indicative), which, thanks also to an area of the frame configured like an elastic element (which compensates for possible size differences of the lens itself), stays rigidly connected to the frame.

BRIEF DESCRIPTION OF THE DRAWINGS

Further characteristics and advantages of the invention will become clearer from the following detailed description, given as an example and illustrated in the attached drawings, where:

Fig. 1 is a top view of one half of an embodiment of the metal frame and of an embodiment of a pad-carrying fastener also made from metal, considering the other half to be the mirror image; Fig. 2 is a top view of a lens;

Fig. 3 is an enlarged view of the pad-carrying fastener with the hook closed; Fig. 4 is a top view of the frame with the lenses inserted, but with the pad- carrying fasteners not closed;

Fig. 5 is an internal perspective view of the half-frame with the lens inserted and application of the pad-carrying fastener;

Fig. 6 is an external perspective view of the half-frame with the lens inserted and partial rotation of the pad-carrying fastener;

Fig. 7 is an external perspective view of the half-frame, with the lens inserted and complete rotation closed of the pad-carrying fastener; Fig. 8 is an internal perspective view of the half-frame, with the lens inserted and complete rotation closed of the pad-carrying fastener;

Fig. 9 is an internal perspective view of the half-frame with the lens inserted and pad-carrying fastener being closed, with the area configured like an elastic element in the foreground;

Fig. 10 is a perspective view of the complete frame assembled with the lenses inserted and the pad-carrying fasteners being closed.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Fig. 1 illustrates just a part of the frame M and a single pad-carrying fastener G, with it being understood that the other part is absolutely symmetrical.

The frame M in its left part has an area C configured like an elastic element, whereas in the right part a half of the upper bridge P is represented, with a throat

P' and a half of the lower bridge Q with an area for receiving the pad-carrying fastener Q'.

The pad-carrying fastener G has a semicircular area with an open hook referred to as G', a sliding area located at the point G'", an edge area G" and a closing area referred to as G"".

Fig. 2 illustrates a lens L, with a central perimeter groove L', suitable for engaging the inner perimeter M' and M" of the half-frame M of fig.1.

Fig. 3 illustrates an enlargement of the pad-carrying fastener G, having the hook

G' closed, on the inside having a section of the receiving area Q', relative to the lower bridge Q; as can be seen from the drawing, once the hook G' is closed, the pad-carrying fastener G will be free to rotate, but it will not be free to detach from the frame.

Fig. 4 illustrates the complete frame M with the lenses L inserted, but with the pad-carrying fasteners not fastened to the upper bridge; thanks to the elastic nature of the frame M and the groove L' made in the lenses themselves, they can stay in their seat even if not rigidly locked by the pad-carrying fasteners (useful function whenever the lenses have to be correctly oriented before they are locked).

Fig. 5 illustrates the first insertion procedure of the pad-carrying fastener G in the half-frame: the pad-carrying fastener G is positioned by matching up the hooked semicircular area G', in the respective receiving area Q' of the lower bridge Q of the half-frame; once the pad-carrying fastener G has been inserted according to the procedure described above, the hook G' will be closed with a simple mechanical operation, according to what is illustrated in fig. 3, thus allowing it to rotate but not to detach. Once locked, it will be made to rotate, according to the direction of the arrow F.

Fig. 6 illustrates the first part of rotation of the pad-carrying fastener G according to the direction of the arrow F': in the first part of rotation the pad- carrying fastener G, hinged in the area G' rotates around the receiving area Q', entering into the throat P' of the upper bridge P, made easier by the curvature in its portion G'".

By continuing with the rotation of the pad-carrying fastener G, according to the direction of the arrow F" of fig.7 and overcoming the resistance given by the edge G" of the pad-carrying fastener G, counteracted by the natural resistance caused by the spreading apart of the bridges P-Q pushed by the lens L, the aforementioned pad-carrying fastener will be in the condition of figs.7-8. The aforementioned edge G' ' of the pad-carrying fastener G will prevent the pad-carrying fastener G from accidentally returning to the condition of fig.6. Fig. 9 illustrates the half-frame assembled with the lens and the pad-carrying fastener, highlighting the area configured like an elastic element C, suitable for compensating for possible size differences of the lenses L. Finally, fig. 10 represents the complete frame with the lenses inserted and locked by the pad-carrying fasteners G.