GB2248507A

GB2248507A - Lens retention system for spectacles

Info

Publication number: GB2248507A
Application number: GB9114166A
Authority: GB
Inventors: Kazimierez Jan Korny
Original assignee: Hellberg International Ltd
Current assignee: Hellberg International Ltd
Priority date: 1990-06-29
Filing date: 1991-07-01
Publication date: 1992-04-08
Also published as: GB9114166D0; GB9014574D0

Abstract

A frame 1, for a single (piano) lens 5, provides aperturing 3 to receive the ions 5 comprising, at least in part, L-shaped recessing, this recessing providing an abutment 7 to the rear surface of the lens. Further portion abutments 11, 13, 15 are provided to engage the front surfaces of the lens and these abutments are provided spaced around the frame 1. The frame carries an upstanding tab e.g. at the area of the nose bridge which in turn carries a rearwardly projecting peg 19 which in passing through a hole in the lens physically couples the lens to the lower part of the frame. The peg 19 may have flexible barbed end which engages the rear face of the lens to resist inadvertent disengagement. Preferably, a tab depending from the brow bar has a rearwardly projecting peg which is also received in a hole in the lens. This ties together the brow bar and nose bridge regions of the frame. <IMAGE>

Description

Title: Lens retention system for spectacles DESCRIPTION The present invention relates to eye wear lens retention, especially for spectacles.

Traditionally spectacle lens retention where a separate lens is provided for each eye is achieved by a combinatiqn of apertures in the frames with inwardly opening V-grooving and lenses whose outer periphery is chamfered to seat in the grooves. The part of the frame forming the apertures is split through which allows expansion for introduction of the lens and is subsequently held closed by a screw action clamp means.

Fitting of lenses by this method is time consuming but for spectacles where there is only infrequent need to remove the lenses the system proves adequate.

For safety or leisure applications, a plano lens (ie. a single lens) can provide useful flexibility to designers where one design of frame may be used with alternative lens configurations and where lenses may have to be replaced from time to time, for example if damaged or to provide different optical properties.

In our co-pending U.K. Patent Application No.

2221551 we have described a lens retention system for retaining a plano lens in a lens holder, eg. a spectacle frame, which provides an aperture to receive the lens having abutment means for front and rear faces of the lens as well as edge retention, and in which clip means is provided which cooperates releasably with a top part of the frame and the lens to hold it in place in conjunction with the aforementioned abutments. The releasable clip means has advantages but adds to the production costs. Accordingly, the present invention aims to dispense with the need for a releasable lens retaining clip whilst ensuring satisfactory retention of the lens.

Accordingly the present invention provides a lens retention system for a spectacle or other eyewear comprising a frame or holder apertured to receive a lens and to provide edge retention therefor, and having abutment means on at least part of said aperturing presenting retention faces to inside and outside surfaces of the lens, and further lens retention means depending from the frame and engaging the lens in a manner to physically couple the lens to the holder, and wherein the lens retention means is releasable from the lens by relative flexion between the frame and lens thereby allowing release of the lens from the aforementioned abutment means, wherein the further lens retention means comprises at least one peg carried integrally with the frame said pin being engageable with a respective through hole in the lens.

Preferably the further lens retention means engages the lens in the region of the nose bridge and preferably comprises a peg or pin carried integrally with the frame and engageable with recessing in the lens. In a preferred configuration the frame or holder has a brow bar and a nose bridge portion with no frame part connecting same in the region of he nose bridge.

In a preferred embodiment the further lens retention means also includes means carried from the brow bar and connecting with the lens. Preferably that means also comprising a peg or pin carried integrally with the frame and engageable in recessing in the lens. More preferably still at least one said recessing and preferably each is a through hole in the lens extending from front to rear surfaces of the lens and the pin extends from a front or rear facing abutment, preferably a rear facing abutment, ie. one engaging a forward/front surface of the lens. A single pin at the nose bridge serves to give edgewise location of the lens to the frame and thereby avoids sagging of the frame in the region of the nose bridge. By providing pins on the nose bridge and the brow bar those parts of the frame are tied together. This is advantageous in meeting lens retention impact requirements.When release is required the frame is flexed to withdraw the pin from the lens.

Preferably the pin has means resisting its removal such as a head or barb-like part at the free end of the pin and engaging the face of the lens.

More particularly a substantial proportion of the aperturing is L-shaped in cross-section to provide edge retention and abutment to one surface of the lens (conveniently the rear surface), whilst further abutments are provided at spaced positions around the aperturing to contact the other surface of the lens.

Prefer ably the aperturing is U-shaped in cross-section at the location of the further abutments, ie. they are provided in addition to the abutment for said one surface.

In a preferred arrangement the L-shaped abutment extends along an upper part of the lens and down the opposite sides. Preferably, the abutment means to said other surface of the lens is disposed at four locations spaced around the aperturing. Firstly, at an upper portion of the frame extending sideways from a central region, at opposite side portions and at the nose bridge. The abutments at the opposite side portions and nose bridge are in substantially alignment horizontally.

The present invention will now be described further, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a side view of a spectacle frame, Figure 2 is a view in the direction of arrow A of Figure 1 showing aperturing of a frame pertinent to the lens retention system of the invention, Figure 3 is a cross-section on XX of Figure 2, Figure 4 is a cross-section on YY of Figure 2, and Figure 5 is a corresponding view to that of Figure 1 for an alternative embodiment.

Referring to the drawings of Figures 1 to 4, the present invention is illustrated by reference to lens retention in a spectacle frame 1 (usually of moulded plastics) having an aperture 3 to receive a plano lens 5 whose outer peripheral shape corresponds substantially with the shape of aperturing 3. The aperturing provides in part, when seen in cross-section, an L-shaped recess providing a forward facing abutment 7 which mates against a rear surface of the lens 5. The frame also has further abutment means for cooperating engagement with a front surface of the lens and these are provided by an upper flange 11 extending widthwise from a central region of the frame and flange parts 13, 15 disposed at opposite side parts of the frame.The flange parts 11, 13 and 15 are placed in front of abutment surface 7 so making the recessing U-shaped over the length of the further flange parts as seen more clearly in Figures 3 and 4.

The frame carries a further upstanding tab 17 disposed in the area of the nose bridge and on a forward facing side of the lens. The tab carries a rearwardly projecting pin 19 (shown in Figures 3 and 4) which passes through a hole in the lens and has at its free end a head or rib to engage a rear surface of the lens.

Such ribbing may be of a semi-resilient nature to enable insertion of the pin through the hole in the lens and to spring out into cooperating engagement with the rear of the lens or after insertion. It will be seen that the pin serves to tie the lens to the lower part of the frame in the region of the nose bridge.

In order to insert a lens it is manipulated into the recessing of the aperture from the rear of the frame engaging the upper edge first, with the lower part of the frame splayed apart to permit entry of the opposite sides of the lens into the side restraints, and whereupon the nose bridge part of the frame is pushed rearwardly to engage the pin in the hole in the lens.

Removal of the lens simply recalls for pulling the nose bridge part of the frame and hence the pin away from the lens and then flexing the nose bridge down and away from the lens. The lens may then be removed from behind the U-sections. Any forward pressure in direction A is taken up by the lens flexing in the U-sections.

Figure 5 illustrates an alternative embodiment and the same reference numerals have been used to denote the parts corresponding to those referred to in the description of Figures 1 to 4 which applies to the embodiment of Figure 5. In this embodiment the flange 11 of the brow bar has a rearwardly projecting peg 21 having a construction preferably corresponding to that for the peg 19 of the nose bridge tab 17, and the lens has a further hole in which the peg 21 is received.

This is advantageous as it locates the brow bar part of the frame in relation to the nose bridge.

Claims

1. A lens retention system for a spectacle or other eyewear comprising a frame or holder apertured to receive a lens and to provide edge retention therefor, and having abutment means on at least part of said aperturing presenting retention faces to inside and outside surfaces of the lens, and further lens retention means depending from the frame and engaging the lens in a manner to physically couple the lens to the holder, and wherein the lens retention means is releasable from the lens by relative flexion between the frame and lens thereby allowing release of the lens from the aforementioned abutment means1 wherein the further lens retention means comprises at least one peg carried integrally with the frame said pin being engageable with a respective through hole in the lens.

2. A lens retention system as claimed in claim 1, wherein said peg has means resisting its removal from the through hole and engaging the surface of the lens.

3. A lens retention system as claimed in claim 1 or 2 in which the lens retention means comprises two pegs, one of which depends from an abutment in the nose bridge region of the frame, and the other depends from an abutment carried from the brow bar, cooperating engagement between the respective pegs and holes serves to link the brow bar of the frame to the nose bridge.

4. A lens retention system as claimed in claim 2 or 3 when appendant on claim 2, wherein said means for resisting removal and engaging the surface of the lens comprises a barb-like end.

5. A lens retention system as claimed in claim 4, wherein the barb-like end is semi-resilient.

6. A lens retention system for a spectacle or other eye wear comprising a frame or holder apertured to receive a lens and to provide edge retention therefor, and having abutment means on at least part of said aperturing presenting retention faces to inside and outside surfaces of the lens, and further lens retention means depending from the frame and engaging the lens in a manner to physically couple the lens to the holder, and wherein the lens retention means is releasable from the lens by relative flexion between the frame and lens thereby allowing release of the lens from the aforementioned abutment means.

7. A lens retention system as claimed in claim 6, the frame having a nose bridge portion and wherein the further lens retention means engages the lens in the region of the nose bridge.

8. A lens retention system as claimed in claim 6 or 7, wherein the further lens retention means comprises at least one peg carried integrally with the frame.

9. A lens retention system as claimed in claim 6 or 7, wherein the lens retention means comprises two pegs, one of which depends from an abutment in the nose bridge region of the frame, and the other depends from an abutment carried from the brow bar, cooperating engagement between the respective pegs and holes serves to link the brow bar of the frame to the nose bridge.

10. A retention system as claimed in claim 8 or 9, wherein the or each peg is engageable with recessing in the lens.

11. A lens retention system as claimed in claim 10, wherein said recessing is a through hole in the lens extending from front to rear surfaces of the lens.

12. A lens retention system as claimed in claim 10, wherein said peg extends from a rearwardly facing abutment.

13. A lens retention system constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings of Figures 1 to 4 as modified according to Figure 5.

14. A spectacle having a lens retention system according to any one of the preceding claims.

15. A spectacle constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings of Figures 1 to 4 or modified according to Figure 5.