Frame for spectacles, particularly of the rimless type, and spectacles comprising such frame

Description Technical scope This invention relates to a frame for spectacles, particularly of the rimless type, according to the characteristics specified in the precharacterising clause of independent claim no. 1. It also relates to spectacles comprising such a frame having the characteristics listed in the precharacterising clause of independent claim no. 21. Technological background

In the technical sector to which this invention relates, spectacles known as rimless spectacles, the frame of which has no lens-holding rims, are known.

In these spectacles the lenses are typically fixed to the frame through a plurality of pins integral with the frame which engage corresponding holes suitably located in the lenses. For example the pins may be secured through a coupling of the screw/nut type, with a nut screwed onto the pin, which in this case is threaded, on the side of the lens opposite the frame. These known arrangements nevertheless have a number of significant disadvantages. The first disadvantage arises from the fact that the surface of the lens opposite the frame is rarely perpendicular to the longitudinal axis of the pin, as a result of which any nut which is screwed onto the pin engages the lens in a very small area of the same, giving rise to relatively high local pressures which are potentially capable of causing cracks and fracture of the lens.

This disadvantage is caused by the fact that the lens surfaces corresponding to the areas where they are normally secured to the frame are often not parallel with each other, in particular in the case of graduated lenses for correcting defects of vision. Not only this, but the angle of inclination of one surface with respect to the opposite surface is not constant and may on the contrary vary widely from one lens to another according to the type and degree of optical correction required.

A second disadvantage found in rimless spectacles constructed according to the known art arises in the fact that where lenses have to be replaced with lenses of greater thickness the pins may be too short to permit the new lenses to be fitted, making it necessary to replace the entire frame.

Description of the invention

The problem underlying this invention is that of providing a frame for spectacles, together with spectacles comprising such a frame, which are structurally and functionally designed to overcome the abovementioned limitations with reference to the cited known art.

This problem is overcome in this invention through a frame and spectacles constructed in accordance with the following claims.

Brief description of the drawings Other advantages and characteristics of the present invention will become clear from the following detailed description which is given with reference to the appended drawings which are provided purely by way of non-limiting example and in which:

- Figure 1 is a perspective view of a portion of a first embodiment of spectacles constructed according to this invention,

- Figure 2 is a view in partial cross-section along the plane II-II of the spectacles in Figure 1,

- Figure 2a is a view in lateral elevation of a first component of the spectacles in Figure 1, - Figure 3 is a view in partial cross-section along the plane III-III of the spectacles in Figure 1,

- Figure 4 is a view in cross-section similar to that in Figure 3 of a second embodiment of spectacles according to the invention,

- Figure 5 is a perspective exploded view of a portion of the frame of the second embodiment of the spectacles,

- Figure 6 is a view in lateral elevation of a first component of the frame in Figure 5,

- Figure 7 is a view in lateral elevation of a second component of the frame in Figure 5, - Figure 8 is a view in partial cross-section similar to that in Figure 3 of a third embodiment of spectacles according to the invention,

- Figure 9 is a view in lateral elevation of a first component of the spectacle frame in Figure 8,

- Figure 10 is a view in lateral elevation of a second component of the spectacle frame in Figure 8,

- Figure 11 is a view in cross-section along the line XI-XI of the component in Figure 10,

- Figure 12 is a view in cross-section similar to Figure 2 of a fourth embodiment according to the invention, - Figure 13 is a view in lateral elevation of a first component of the

spectacle frame in Figure 12.

Preferred embodiment

In the appended figures, 1 indicates as a whole a pair of spectacles constructed in accordance with this invention. Spectacles 1 comprise a frame 2 on which are fixed lenses 3. Frame 2 is of the rimless type, that is it has no lens-holding rims, and comprises a frame

2a including a bridge extending between the two lenses and a pair of connecting members 4 which connect frame 2a in an articulated way with a pair of sides 5 which are in themselves conventional. In accordance with conventional procedure, lenses 3 may be attached to frame 2 at connecting members 4 and the bridge of frame 2a through securing means indicated as a whole by 6.

In the description which follows, as in the appended figures, reference will be made to the securing means located on connecting member 4, but it should be understood that these securing means may similarly be provided on the bridge of the frame.

Securing means 6 comprise. a first securing member which with reference to the embodiments illustrated in Figures 1 to 11 comprises a threaded pin 7 extending from the frame towards lens 3 along a longitudinal axis X. Pin 7 is received within a seat formed by a hole 8 passing through the lens and held in the hole by a second securing member comprising a nut 9 screwed onto pin 7 on the side of lens 3 opposite frame 2.

In order to prevent the possibility of fracturing lens 3, direct contact between -the components of frame 2, which is typically manufactured of metal, and the lens itself is avoided. Provision is therefore made for a pair

of washers 9a, 9b to be located between nut 9 and lens 3 and for a sleeve 8a located between pin 7 and lens 3 to be inserted in hole 8. Sleeve 8a also comprises a flange 8b, abutting lens 3 at the opening of hole 8, thus lying between connecting member 4 and lens 3. Washers 9a, 9b and sleeve 8a are conveniently constructed of material which is soft in relation to the material of which the frame and lenses are made, for example a thermoplastic material such as polyamide. In addition to damping and distributing the nut tightening load, the provision of two separate washers 9a, 9b advantageously makes it possible to avoid any tangential slip of nut 9 with respect to the surface of lens 3, as a result of the friction between them.

A hinge 11 is provided adjacent to pin 7 in order to hinge side 5 to connecting member 4, which is placed in a recess 12 made in the perimetral edge of lens 3 so as to prevent any rotational movement with respect to member 2a of frame 2.

Opposing main surfaces are defined on lens 3, one of which, indicated by 13, faces frame 2, and the other, indicated- by 14, faces the opposite way. As is clearly shown in Figure 2, surfaces 13 and 14 are not parallel to each other. According to a principal aspect of this invention, pin 7 is secured to connecting member 4 at a head 15 through a coupling of the hinged type so that it can move back and forth with respect to connecting member 4 around a hinge axis Y substantially perpendicular to the longitudinal axis X of pin 7.

Preferably sleeve 8a is dimensioned so that it itself constitutes the maximum limit for the turning of pin 7 about the Y axis. Head 15 of pin 7 is secured to a sleeve 16 firmly secured to connecting member 4 through a hinge member. Sleeve 16 comprises a pair of projections 17 and 18 extending parallel to the X axis, between which head

15 of pin 7 is located. Preferably projections 17, 18 are located on opposite sides of head 15 along hinge axis Y and are located in recesses 19, 20 respectively made in head 15.

The function of projections 17, 18, acting together with corresponding recesses 19, 20, is to support and hold head 15, preventing the latter from moving along hinge axis Y and from rotating about axes other than the Y axis.

For this purpose a stop surface 21 is provided on each projection 17, 18, which is for example planar and substantially perpendicular to hinge axis Y, abutting against a corresponding surface 22, which for example is also planar, formed in recesses 19, 20.

A certain amount of play is provided between the extremities of projections 17, 18 and shoulders 22a bounding recesses 19, 20 so as to allow pin 7 to move back and forth with respect to sleeve 16. As an alternative it is provided that the extremities of projections 17, 18 and shoulders 22a of recesses 19, 20 are suitably rounded.

According to a first embodiment of the invention, illustrated in detail in Figures 2 and 3, the hinge member through which pin 7 is secured to sleeve

16 comprises a pin 23, having an axis Y, which is removably inserted into holes 24, 25 and 26 made in projections 17, 18 and head 15 of pin 7

respectively.

Lens 3 is mounted on frame 2 by inserting pin 7 through hole 8, in which sleeve 8a has previously been fitted, and then by screwing nut 9 on pin 7 so as to tighten lens 3 against connecting member 4. It will be noted that in the course of the tightening action nut 9 tends to cause pin 7 to rotate about the Y axis as it comes into contact with surface 14 of lens 3 in such a way as to bring longitudinal axis X of pin 7 into a perpendicular position with respect to surface 14 of lens 3. For this purpose hole 8 and sleeve 8a are dimensioned to have a diameter which is suitably greater than that of pin 7. Rotational movement of pin 7 ends when the condition of perpendicularity defined above is reached, or when pin 7 abuts against sleeve 8a.

It is obvious that the final condition of perpendicularity between the X axis and surface 14 makes it possible to distribute the tightening load of nut 9 over the maximum possible surface area of lens 3, so that the possibility of fracturing lens 3 caused by excessive pressure concentration is substantially reduced.

Once nut 9 has been tightened, any excess portion of pin 7 can be conveniently cut off so as not to project excessively from surface 14 of lens 3 (see Figure 2).

It will also be appreciated that pin 7 can easily be removed from frame 2, simply by removing pin 23 and sliding head 15 off sleeve 16. Through this pin 7 can be replaced by another pin of greater length if necessary, for example when lens 3 in turn has to be replaced by a new lens of greater thickness.

In a second embodiment of the invention, illustrated in detail in Figures 4 to 7, in which similar components are identified by the same reference numbers as in the previous example, the hinge member comprises an appendage 27 which is of one piece with pin 7 and extends from recess 19 in head 15 parallel to hinge axis Y. Appendage 27 is housed in a hole 28 provided in projection 17. It will be noted that in this case projection 18 extends to a lesser extent than projection 17 in order to assist the operation of inserting head 15 between projections 17, 18, and consequently recess

20 receiving it is also shorter. In a third embodiment illustrated in Figures 8 to 11, in which similar components are identified by the same reference numbers as in the previous example, the hinge member comprises a pair of appendages 29, 30 extending symmetrically from recesses 19, 20 along hinge axis Y and slidably located in corresponding grooves 31, 32 made in projections 17, 18. Grooves 31, 32 extend from one side of projections 17, 18 towards a median zone thereof in an insertion direction Z along which head 15 is guided when engaged between projections 17, 18.

Preferably insertion direction Z is inclined with respect to the longitudinal axis X of pin 7 in such a way that the median zone is further from connecting member 4 than the opening of the groove on the side of the projection. In this way, once guided towards the median zone, head 15 is held in position by the tensile force exerted on pin 7 through tightening nut 9. Of course the line of grooves 31, 32 may be different from that shown by way of example, provided that the final section thereof adjacent to the median zone where appendages 29, 30 are positioned in . an operating

configuration is at a distance from connecting member 4. For example the grooves may have an L-shaped line, with a first limb perpendicular to the X axis and a second limb parallel thereto, extending away from connecting member 4. Grooves 31, 32 are blind, that is they are provided with an end wall, however in a variant embodiment which is not shown provision is also made for one or both of grooves 31, 32 to be open, thus forming corresponding through channels within which appendages 29, 30 are guided. In a fourth embodiment of the invention, illustrated in detail in Figures 12 and 13, in which similar components to those in the previous examples are identified by the same reference numbers, the first securing member, here indicated as a whole by 33, instead of being a solid pin provided with an external thread comprises a blind seat 34 provided axially along longitudinal axis X and open at the extremity opposite head 15. Seat 34 is threaded internally, so that a screw 35 comprising the second securing member of means 6 can be received therein so that lens 3 can be secured to frame 2. In the example illustrated here, head 15 has the shape of pin 7 in the second embodiment of the invention (Figures 4 to 7), but it is to be understood that this may similarly have any of the other shapes described above with reference to the other examples.

Preferably hole 8 made in lens 3 to receive the first securing member has two adjacent sections of different cross-section, 36, 37. The first section 36, close to head 15, has a smaller cross-section and sleeve 8a of thermoplastic material is housed therein. Second length 37 on the other hand, in which the portion of first securing

member 33 in which seat 34 is provided is housed, has an elliptical cross- section, in the form of an eyelet, elongated in the direction of the plane perpendicular to hinge axis Y. In this way the back and forth movement of first securing member 33 around the hinge axis is not obstructed by the walls of hole 8.

If lens 3 is replaced by a lens of different thickness, in particular one of greater thickness, it will not generally be necessary to replace first securing member 33, but only screw 35. Furthermore, advantageously, first securing member 33 will be dimensioned in such a way as to be of shorter length than the thickness of the thinnest lenses normally commercially available. This invention thus resolves the problem described above with reference to the cited known art, while at the same time offering many other advantages.