Frame for spectacles with arms that can be resiliently spread apart. Technical field

The subject of the present invention is a frame for spectacles with arms that can be resiliently spread apart according to the preamble of main claim 1. Technological background

The invention is placed in the specific field of frames for spectacles equipped with systems for articulation of the arms by means of which the arms may be pivoted beyond the normal open position, though returned to that position when released.

In this field it is known to produce frames typically provided with a tie-rod hinged to the articulation lug of the arms and slidably associated with the arm, and with one or more springs acting between the tie-rod and the arm. In these specific applications, there is a need to obtain a high degree of robustness and mechanical strength as well as considerable durability of the hinge members, characteristics which are desired in frames including arms of large size and heavy weight, even though distinguished by rather slender profiles, at least to a limited extent in one of the dimensions of the cross-section of the arm.

In order to fulfil such requirements, a frame solution has for example been proposed in which each of the arms is provided with a pair of springs. This solution is the subject of International Patent

Application PCT/IT2006/000504, in the name of the same Applicant. In this solution, each arm is provided with a pair of tie-rods and a pair

of helical springs, each spring acting between the arm and one of the tie-rods. Each spring further has a flattened configuration, in which the axes of the coils are inclined with respect to the longitudinal direction of the spring, there being thus identified a respective notional plane containing that direction and approximately oriented along the main surface of flattening of the spring. In the solution described, the respective planes of flattening of the springs of each arm are parallel to and spaced from one another, and also extend perpendicularly to the hinge axis. This solution does not lend itself well to being applied to arms of frames in which a marked slendemess of the arm in the direction of the hinge axis is required, and consequently such as to require arm cross-sections of extremely small overall dimensions in a direction perpendicular to the hinge axis. Frames of the aforesaid type normally provide front lens-holding mounts of large dimensions on which are articulated lugs for arms with consequently high arm heights (understood as the dimension of the arm cross-section measured parallel to the hinge axis of the arm), so as to impart suitable and notable appeal to the spectacles. On the other hand, since slendemess of the arm in a direction perpendicular to the hinge axis is required, and also adequate robustness and durability of the resilient hinge mechanism, the aforesaid solution with double spring has limitations for application in these specific frames. Description of the invention The primary aim of the present invention is that of providing a

frame for spectacles with arms that can be resiliently spread apart which is structurally and functionally designed to remedy the aforesaid limitations, and in particular to obtain greater resilient strength in the arm, together with suitable robustness and durability of the hinge. This aim and others identified hereinafter are achieved by the invention by means of a frame for spectacles which is produced according to the attached claims. Brief description of the drawings

The characteristics and advantages of the invention will become clearer from the following detailed description of a preferred exemplary embodiment thereof, illustrated by way of non-limiting example with reference to the appended drawings, in which:

Figure 1 is a perspective view of a frame produced according to the present invention, - Figure 2 is a partial plan view, on an enlarged scale, of a detail of the frame of Figure 1,

Figure 3 is a partial view in side elevation of the detail of Figure

2,

Figures 4 and 5 are views respectively in plan from above and in side elevation of a detail of Figure 2,

Figures 6 and 7 are views respectively in plan from above and in side elevation of a further detail of Figure 2,

Figure 8 is a plan view from above of a detail of Figure 2,

Figure 9 is a view in section along the line IX-IX of Figure 8, - Figure 10 is a plan view from above of a further detail of Figure

2,

Figure 11 is a view in section along the line XI-XI of Figure 10, Figures 12 and 13 are views respectively in plan and in side elevation of a detail of the frame of Figure 1, - Figures 14 and 15 are perspective views of details of the frame of Figure 1. Preferred embodiment of the invention

With reference to the drawings mentioned, the reference 1 indicates as a whole a frame for spectacles with arms that can be resiliently spread apart produced according to the present invention.

The frame 1 comprises arms 2 having a longitudinal axis X (understood as the longitudinal direction of the arm), articulated on respective lugs 3 of a front mount, indicated as a whole by 4.

A description will now be given of the resilient hinging system of only one of the arms 2, it being understood that the other arm, symmetrical in mirror image, is articulated in a structurally and functionally identical manner.

In the arm 2 a tie-rod member indicated by 5 is provided, hinged to the lug 3 via a threaded pin 6, about a hinge axis Y, substantially perpendicular to the direction of the axis X. The tie-rod 5 is part of a respective device for resilient return of the arm, acting on the arm, and described in detail hereinafter. The tie-rod 5 comprises a head 7 provided with a through-hole 8 for receiving the pin 6 and a stem 9 extending axially from the head 7. The stem 9 has a rectangular cross-section and is slidably associated with the arm 2.

For the hinged articulation of each tie-rod 5 by means of the respective pin 6, the lug 3 is provided with respective pairs of plate- like wings 3a, extending parallel to and spaced from the lug in order to receive between them the respective head 7. Said pairs of wings are provided with respective through-holes coaxial with one another and with the hole 8 in the head when hinged on the lug. One of the holes may conveniently be threaded for the engagement by screwing of the threaded pin 6. Provision is made for the wings 3a to be obtained in one piece in the front mount 4 or, alternatively, to be part of a separate hinge member arranged to be fixed to the front mount.

At the end of the stem 9 axially opposed to the head, the tie-rod 5 is extended in a plate-like portion 9a from which stand up in the same direction a pair of appendages 11, parallel and spaced and also conveniently configured as a pin, for coupling respective axial ends of a pair of helical springs, both indicated by 12, the opposite ends of which are secured to the arm 2. The springs are preferably both structurally and functionally identical.

Each spring 12 is of helical type and extends in a respective prevalent longitudinal direction K', K" substantially parallel to the axis X. Each spring 12 is preferably produced from metal wire and comprises a plurality of coils 12a which have respective coil axes parallel to one another, all indicated by L, and inclined with respect to the corresponding axis K', K", with an angle A being identified, contained between the directions K', K" and L As a result of that inclination, the coils 12a impart to each spring 12 a substantially

flattened configuration overall, as can be seen from Figure 3, transversely to the corresponding direction K', K".

Each spring 12 therefore appears "squashed" in a predetermined lateral direction so as to assume, in that direction, a lesser transverse overall dimension, with respect to a conventional helical spring of equal wire diameter and equal diameter of the coils.

In more detail, with reference to Figure 14, it is possible to identify a notional plane of prevalent flattening of the spring, indicated by P and extending perpendicularly to the plane Q containing the coil axes L (parallel to and coplanar with one another) and the longitudinal direction K', K", as highlighted in the aforesaid figure.

According to a principal characteristic of the invention, with particular reference to Figure 15, the directions K ¹ and K" are parallel to and spaced from each other and the springs 12 assume their flattened configuration in the same common plane P of prevalent flattening, with the hinge axis Y directed substantially parallel to the common plane P of prevalent flattening. Figure 15 clearly illustrates said configuration in which the springs 12 end up, in other words, "squashed" in the same common plane P of flattening and the hinge axis Y is directed parallel to that plane, thus rendering the springs approximately coplanar, as can be seen from the aforesaid figure, the squashing being therefore obtained in a direction transverse to the hinge axis, so as to reduce in that direction the overall lateral dimensions of the arm. direction. As clearly shown in the drawings, provision is also made for the

longitudinal directions K', K" of the springs to be directed parallel to the longitudinal direction of the arm, identified by the direction of the axis X of the drawings.

At the opposed axial ends of each spring 12, the corresponding coils are bent back to assume a configuration like an open eyelet portion 12b, capable of engaging in the respective coupling formations provided in the tie-rod (appendages 11) and in the arm.

The frame 1 further comprises, for each arm 2, a tubular casing, indicated by 13, in which the springs 12 and the tie-rod 5 are received, slidably guided in the inner cavity of the casing.

In more detail, the casing 13 containing the respective springing device has a tubular configuration with substantially rectangular cross- section, of dimensions suitable to receive, with slight clearance, the springs 12 (alongside one another) having the flattened configuration described above.

The axial end of each spring 12 furthest from the lug is coupled in a respective pin formation 15. Said pin formations 15 stand up in the same direction from a base 16a of a support 16 arranged to be slidably received in the tubular cavity of the casing 13, and rigidly secured to same, in a preselected position during the assembly of the arm on the frame. A threaded hole 17 is conveniently provided, passing through the base 16a of the support, for the engagement of a screw with which the support 16 is secured to the corresponding tubular casing 13. On this latter, a hole 17a is provided for the passage of the screw for clamping to the support.

The reference 18 indicates a stem-like portion protruding from the support 16 and arranged to be secured to an end part 19 of the arm, extending in axial extension of the casing 13, in the direction X, and capable of supporting the spectacles on the head in the region of the ears.

The portion 18, preferably in the shape of a pin, constitutes at least part of the core of the end part 19 of the arm 2 and may conveniently be covered at said end part by over-moulding.

Returning to the tie-rod 5, the stem 9 of same is engaged such as to slide axially, in a guide member 20, removably secured to the casing 13. Said member comprises a plate-like base 20a from which stand up in the same direction a pair of shoulders 21 in a spaced relationship, between which shoulders the stem 9 is slidably guided with slight transverse clearance. The guide member 20 may be simply inserted into the casing 13 with a movable coupling (that is, not fixed in), since its position in the casing is constantly ensured by the pressure exerted on this latter by the surfaces of the lug. Alternatively, the guide member 20 may be secured to the casing 13 via an interference coupling, by means of pressure engagement in the tubular cavity of the casing, at one of the axial ends of same, for the purpose of facilitating the operations of assembly of the arm, preventing the guide member 20, once inserted into the casing 13, from accidentally escaping therefrom before being secured to same.

At the free end associated with the guide member, the casing 13 further has a surface 23 capable of locating a corresponding abutment

surface of the lug 3 and serves to locate this latter when the arm 2 is pivoted beyond the normal opening position.

In the stage of assembly of the frame 1, the guide 20 is previously slidably coupled on the tie-rod, the springs 12 are coupled to the pins 11 of the tie-rod and to the pins 15 of the support, and the assembly consisting of these members is inserted into the tubular casing 13.

The springs 12 are then biased in elongation by means of axial displacement of the support 16 relative to the casing and subsequent mutual locking, by means of engagement by screwing a screw into the hole 17. The support 16 is then secured to the end part of the arm.

The arm 2, complete with tie-rod, guide, pair of springs and support, is coupled to the front mount 4 by insertion of the hinge pin 6 in the devices for articulation of the arm. The guide 20 is further rigidly connected to the tubular casing 13. In this state, the casing 13 is abutted against a locating means 5a of the tie-rod and the overall resilient bias induced in the springs imparts the resilient behaviour of the corresponding device.

The resilient return of the springs 12 to assume the initial length at rest is transferred into the hinge articulation and the arm is provided with the capability of spreading out resiliently beyond the normal opening position by rotating through an additional angle, the magnitude of which is determined by the relative axial travel between the guide member and the respective tie-rod towards an opposed raised portion 5b of the tie-rod which therefore functions as a limiter

for the additional pivoting of the arm.

In fact, when the arm 2 has pivoted beyond the normal opening position, following the location of the surface 23 with the lug 3, relative sliding occurs between the tie-rod and the guide (and consequently between the tie-rod and the arm) with consequent further elongation of the springs 12, which induces an additional resilient return action of the arm into the normal open position when the arm is released.

It should be noted that the arm 2, at the springing device, has extremely small overall lateral dimensions, mainly linked to the squashed configuration of the springs 12 and to their substantially coplanar state.

Moreover, owing to the tubular configuration of the casing for containing the aforesaid devices, the whole of the components of the resilient hinging device can be nested inside the tubular casing, thus limiting the external overall dimensions to the advantage of slenderness of the arm. Last but not least is the advantage of obtaining an increased overall lightness of the arm, due in particular to the tubular structure of same.

Owing to the provision of a pair of springs, there is greater resilient strength in the return device, besides the fact of obtaining greater mechanical strength of the hinges, which has the effect of greater overall robustness of the hinge articulation, with consequently greater durability over time.

This property of greater robustness and durability of the resilient hinges therefore advantageously combines with a high degree of

slenderness of the arm, in a direction transverse to the hinge axis, so as to make it possible to house the resilient device also in arms of spectacles of increased height (measured in the direction parallel to the hinge axis) but of small overall transverse dimensions (perpendicular to the hinge axis), a structure which distinguishes spectacle frames known to have a particular aesthetic appeal.

The invention thus achieves the aims proposed, obtaining the advantages claimed above compared with the known solutions.

Among these are numbered a greater mechanical strength (robustness) of the hinges, greater durability over time, and greater resilient strength (force) of the resilient return mechanism of the arm, aspects which are added to the advantage of being able to differentiate the design of the frames with respect to the styles well known up to now, owing to the greater versatility of the resilient hinges according to the invention, which lend themselves to being mounted, in a reliable and durable manner, also on arms of greater weight and dimensions, yet distinguished by more slender and lighter geometry overall.