BACKGROUND OF THE INVENTION [00021 Eyeglasses are of course a well-knovn expedient to correct defects in the vision of the wearer. Eyeglasses are also used to shield the eyes of the wearer from adverse conditions, particularly bright sunlight. l00031 For users of eyeglasses with corrective lenses, it is not unusual to provide additional auxiliary lenses that can be attached over the lenses of the corrective eyeglasses to provide protection against sunlight. Typically, the auxiliary lens is secured by mechanical clips but difficulty in attaching the clips has led to the adoption of magnetic retention for the auxiliary lens.

(0004] In normal use, the auxiliary lens will either be attached to or detached from the primary lens as the ambient light conditions vary. However, in certain situations, such as when driving a vehicle, it is desirable to retain the auxiliary lens on the primary lens even when the auxiliary lens is not required. Mechanical hinge arrangements that allow the auxiliary lens to be "flipped up"relative to the primary frame are known and in widespread use. such arrangements require mechanical connection to the primary lens and the provision of a hinge mechanism at the bridge of the frame to allow for the adjustment of the auxiliary lens relative to the primary lens. One prior art solution is shown is US patent 3,531, 188 to Leblanc in which an auxiliary lens assembly is secured by clips to the spectacle with a hinge-to permit the auxiliary lens assembly to be moved between a covered and uncovered position of the primary lens. In the Leblanc patent, the auxiliary lens assembly is secured by clips that not only are difficult to assemble but also suffer the risk of damaging the surface of the primary lens. Moreover, with the auxiliary lens assembly in a position to uncover the primary lens, the retaining clips are visible and therefore unattractive.

[0005] It is therefore an object of the present invention to obviate or mitigate the above disadvantages.

[0006) In accordance with one aspect of the present invention there is provided an eyeglass having a primary frame and an auxiliary frame. The frames are secured to one another by interaction of magnetic members on the frames. The frames and magnetic members are configured to be operable to maintain the frames in a first orientation in which the auxiliary frame overlies the primary frame and in a second orientation in which the auxiliary frame is disposed above and away from the optical axis of the lenses of the primary frame.

BRIEF DESCRIPTION OF THE DRAWINGS [00071 Embodiments of the invention will now by described by way of example only with reference to the accompanying drawings in which : [0008] Figure 1 is a perspective view of a primary frame.

[0009} Figure 2 is a rear perspective view of an auxiliary frame.

[00101 Figure 3 is perspective view showing the primary and auxiliary frames assembled.

[0011] Figure 4 is a view on the line 1V-IV of Figure 3 in a first orientation of the frames.

[0012] Figure 5 is a view similar to Figure 4 with the frames disposed in a second orientation. tOO131 Figure 6 is a view similar to Figure 4 of an alternative embodiment of the frames.

[00141 Figure 7 is a view of the embodiments shown in Figure 6 with the frames disposed in an alternative orientation.

[0015) Figure 8 is a view similar to Figure 4 of an alternative embodiment. iOOlSj Figure 9 is a view of the embodiment of Figure 8 in an alternative configuration of frames.

[00171 Figure 10 is a view similar to Figure 4 of a still further embodiment.

0018] Figure 11 is a view of the embodiment of Figure 10 in an alternative configuration.

(0019J Figure 12 is a perspective view similar to Figure 1 of a still further embodiment of eyeglass.

(00201 Figure 13 is a rear perspective view of an auxiliary eyeglass for use with the primary frames of Figure 12.

[0021] Figure 14 is a rear view of a portion of the frame in Figure 12 with the auxiliary frame attached in a first orientation.

[0022] Figure 15 is a view similar to Figure 14 with the auxiliary frame in a second orientation.

[0023] Figure 16 is a view on the line XVt-XVI of Figure 14.

[0024] Figure 17 is a view on the line of Figure 18 XVII-XVII.

[0025J Figure 18 is a cross sectional view of a further arrangement.

00261 Figure 19 is a view similar to Figure 18 of a still further arrangement.

(0027] Figure 20 is a view similar to Figure 18 of a further embodiment.

[0025] Figure 21 is a view of the embodiment of Figure 20 in an alternative configuration.

100291 Figure 22 is a view of the embodiment of Figure 0 in a further configuration.

(0030] Figure 23 is a view similar to Figure 19 of a still further embodiment.

[0031] Figure 24 is a view similar of a yet further embodiment applied to a bridge of an eyeglass, [00321 Figure 25 is a plan view of the eyeglasses shown in Figure 24.

[0033] Figure 26 is a section on the line XVI-XVI of Figure 25.

[0034] Figure 27 is a sectional view similar to Figure 26 of a further embodiment.

[0035] Figure 28 is a sectional view similar to Figure 26 of a still further embodiment.

[0036] Figure 29 is a sectional view similar to Figure 26 of a yet further embodiment.

[0037j Figure 30 is a perspective view similar to Figure 24 of a further arrangement of eyeglass.

[0038] Figure 31 is a plan view of the arrangement shown in Figure 30.

[0039] Figure 32 is a sectional view similar to Figure 26 of a further embodiment of the arrangement shown in Figure 30.

10040] Figure 33 is a perspective view of a further embodiment of eyeglass.

[0041] Figure 34 is a detailed view of a portion of Figure 33 on an enlarged scale.

[0042] Figure 35 is a section on the line 35-35 of Figure 34.

[0043] Figure 36 is view similar to Figure 35 of a alternative embodiment of the arrangement shown in Figure 34.

[0044] Figure 37 is a section on the line 37-37 of Figure 36.

[0045] Figure 38 is a further embodiment of the arrangement shown in Figure 34.

[0046] Figure 39 is a view on the line 39-39 of Figure 38.

[0047] Figure 40 is a still further embodiment of the arrangement shown in Figure 34.

10048, 1 Figure 41 is a section on the line 41-41 of Figure 40.

[0049] Figure 42 is a further view similar to Figure 34 of a further embodiment.

10050) Figure 43 is a section on the line 43-43 of Figure 42.

[0051] Figure 44 is a view similar to Figure 34 of a still further embodiment.

[00521 Figure 45 is a view on the line 45-45 of Figure 44.

[0053] Figure 46 is a view similar to Figure 34 of a further embodiment.

[0054] Figure 47 is a sectional view on the line 47-47 of Figure 46.

[0055] Figure 48 is a front elevation of a pair of spectacles in accordance with a further embodiment.

[0056] Figure 49 is a front elevation of an auxiliary lens assembly for use in the embodiment of Figure 48.

00571 Figure 50 is a plan view of the spectacle shown in Figure 48.

[0058] Figure 51 is a plan view of the auxiliary lens assembly shown in Figure 49.

[0059) Figure 52 is a front elevation of the eyeglasses formed from a combination of the spectacles of Figure 48 and the auxiliary lens assembly of Figure 49.

[00601 Figure 53 is a plan view of Figure 52.

[0061] Figure 54 is a view on the line IIV-IIV of Figure 53 on a larger scale.

[00621 Figure 55 is a view similar to Figure 54 partly in section.

100631 Figure 56 is a detailed view of a first alternative embodiment to the arrangement shown in Figure 54.

[0064] Figure 57 is a view similar to Figure 56 of a second alternative embodiment to that shown in Figure 54.

10065] Figure 58 is a side view similar to Figure 54 of an alternative configuration.

Figure 59 is a view similar to Figure 54 of a further alternative configuration.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 10066l Referring therefore to Figure 1, eyeglasses 10 includes a primary frame 12 having a pair of lens openings 14,16 interconnected by a bridge 18. Corrective lenses 20,22 are received in the openings 14,16 respectively.

[0067] Side arms 24, commonly referred to as temples, are connected by a hinge 26 to the temple region 28 of the primary frame. The temple region 28 is formed at the intersection of an upper frame member 30 and lens rim loop 32. It will be appreciated that the frame member 30 and rim loop 32 are moulded to provide a unitary construction although alternative constructions using individual components are envisaged within the scope of the invention.

[00681 The upper frame member 30 has an upwardly directed surface 32 that extends into the temple region 28. A notch 34 is formed in the upper surface 32 adjacent to but inwardly spaced from the end 36 of the temple region 28. As seen in Figure 4, the notch extends across the main frame member 32 so as to intersect the front and rear surfaces 38,40 of the main frame member 30. A magnetic insert 42 is located in the notch 34 and secured by adhesive, mechanical connection or the like. The magnetic insert 42 may be a magnet or may be a magnetic material that is attracted to a magnet. The magnetic insert 42 conforms to the profile of the main frame member 30 and has a forwardly directed surface 44 and an upwardly directed surface 46. The surfaces are flush with or slightly proud of the adjacent surface of the upper frame member 32.

[0069] The spectacles 10 include an auxiliary frame 50 as shown in Figure 2. The auxiliary frame 50 has a shape complimentary to that of the primary frame 12 having a pair of lens openings 52, 54 interconnected by a bridge 56. Tinted lenses 58, 60 are located within the lens openings 52, 54. Temple regions 62 project laterally from opposite ends of a main frame member 64 and each has a rearwardly directed surface 66. The surface 66 carries a magnetic member 68 having an outer surface 69 that may be mounted on the surface 66 or accommodated within a recess formed in the surface 66. The magnetic member 68 may be either a magnet or a magnetisable material attracted by a magnetic force when the insert 42 is itself a magnet. The magnetic member 68 is positioned so as to coincide with the location of the notch 34 and therefore the magnetic inserts 42 on the upper frame member 30 of the primary frame 12.

[00701 In use, the auxiliary frame 50 may be located in front of the primary frame 12 with the surfaces 44, 66 in abutment to provide protection for the user and is secured by interaction between the magnetic inserts 42 and magnetic member 68. As noted above, at least one of the magnetic inserts 42, and magnetic member 68 must be a magnet and the other either a magnet or magnetisable material to ensure that the auxiliary frame 50 is retained on the primary frame 12.

With the auxiliary frame in position, the tinted lenses 58, 60 provide additional protection to the user.

100711 If the protection afforded by the lenses 58, 60 is no longer required, the configuration of the frames 12,50 and magnetic inserts 42 enables the auxiliary frame SO to be moved to an alternative position illustrated in Figure 5. The lenses 58, 60 are moved up and out of the optical axis of the lenses 20,22 but the auxiliary frame 50 is retained on the primary frame 12. As shown in Figure 5, the auxiliary frame 50 may be rotated through 90° so that the surface 69 of magnetic member 68 is moved into abutment with the upwardly directed face 46 of the magnetic insert 42. Ln this position, the magnetic forces serve to maintain the auxiliary frame 50 in a stable position. The disposition of the forwardly directed faces 44 and the upwardly directed face 46 at 90° to one another provides a pair of stable positions to support the auxiliary frame.

The faces 44, 46 provide a pair of abutment surfaces that are positioned to contact the magnetic member 68 at the respective stable positions and thereby retain the auxiliary frame on the primary frame. The planar nature of abutment surfaces 44,46 inhibits relative movement due to shock loads imposed on the auxiliary frame in use.

100721 An alternative embodiment is shown in Figure 6 where like reference numerals will be used with like components with a suffix"a"added for clarity. In the embodiment of Figure 6, the magnetic member 68a is arranged to project rearwardly from the temple 62a. Insert 42a provides a first stable position in which the magnetic member 68a engages the upwardly directed surface 46a of the insert. In this position, the auxiliary frame 50a is maintained overlying the primary frame 12a.

10073 In an alternative position shown in Figure 7, the magnetic member 62a engages a rear face 48 of the magnetic insert 42a with the auxiliary frame projecting outwardly from the main frame 12a.

[0074] A further embodiment is shown in Figures 8 and 9 in which the notch 34b is provided on the underside of the temple 28b. The magnetic member 68b projects rearwardly from the beneath the temple 62b so as to engage a downwardly directed surface 49b of the insert 42b. In this position the auxiliary frame 50b is maintained in a stable position overlying the primary frame 12b.

(0075] To move the auxiliary frame 50b to an alternative position shown in Figure 9, it is rotated through 90° so that the magnetic member 68b engages the forwardly directed face 44b of the magnetic insert 42b. The magnetic forces between the insert 42b and the magnetic member 68b maintain the primary and auxiliary frames in stable position with the main frame member of the auxiliary frame 50b overlying the upper surface 32b of the main frame member 30b.

10076l A further embodiment is shown is Figures 10 and 11 in which the magnetic member 68c is formed as an L-shaped arm that projects rearwardly from the temple 62c. The distal end of the L-shaped arm engages a rearwardly directed face of the insert 48c to hold the auxiliary and primary frames in stable position. To move the auxiliary frame to an alternative position out of the optical axis of the lenses 20,22, the auxiliary frame 50c is rotated through 90° causing the L- shaped arm to engage the downwardly directed and forwardly directed faces 49c, 44c respectively of the insert 42c. The main frame member 64c of the auxiliary frame 50c overlies the upper surface 32c of the main frame member 30.

[0077] In each of the above embodiments, a pair of stable surfaces is provided to support the main and auxiliary frame members.

100781 ln a further embodiment shown in Figures 12 through 15, the magnetic insert 42d is provided on the end face 36 of the temple 28d. In this arrangement, the auxiliary frame 50d has the magnetic member 68d projecting reanvardly and lying in a generally vertical plane. The spacing between the magnetic member 68d corresponds to the spacing between the end faces of the inserts 42d so that the auxiliary and main frames are connected by the magnetic forces between the insert 44d and the magnetic member 68d. As can be seen in Figures 16 and 17, the temple 28d of the main frame 12e is formed with a pair of planar faces 70,72 that provide a pair of stable supports for the auxiliary frame 50e. The interaction between the main and auxiliary frame members provides a pair of stable positions as the auxiliary frame is rotated from a position in which it overlies the primary frame to the position in which it projects above and forwardly of the primary frame. Magnetic forces between the magnetic plate 68d and the inserts 44d ensure retention of the auxiliary frame on the primary frame and the shape of the magnetic inserts and upper frame member provide the two stable positions.

[00791 Alternative cross sections of the inserts may be utilised to provide a pair of stable positions. Similarly, the stable positions may be provided by interaction with surfaces of the frame members 30, 64 where the insert does not provide a pair of stable positions or by the insert itself where the frame does not provide a pair of stable positions.

100801 As seen in Figure 18, the front face 70e and upper face 72e of the primary frame 12e may be used to provide stable positions for the auxiliary frame 50e in a manner similar to Figure 14 to 17. In the embodiment of Figure 18, the magnetic member 42e is a circular bar located within the notch 34e. The magnetic member 68e projects rearwardly from the auxiliary frame 50d and has a semi-circular recess 74 that is complementary to the outer surface of the magnetic member 42e. The magnetic members 42e, 68e thus provide a pivot to allow the auxiliary frame 50d to move between the stable positions provided by the faces 70e, 72e, on the frame 12d. The rearwardly facing surfaces of the auxiliary frame to either side of the magnetic member 68e are planar to corporate with the faces 70e, 72e and support auxiliary frame 50d in either position.

{0081) A similar arrangement is shown in Figure 19 where the outer surface of magnetic member 42f is semi-circular and tangential to the adjacent surfaces 70f 72f of the temple 28f.

The magnetic member 681 is a plate that engages the magnetic member 42f in each of the stable positions.

10082] In each of the above embodiments a pair of stable positions disposed at 90° to one another has been provided. Additional stable positions may be incorporated as indicated in the embodiments of Figures 20 to 22 and 23.

[0083] In the embodiment of Figure 20 to 22 an arrangement similar to that of Figure 18 is utilised. However, in this embodiment the magnetic member 42g is formed as an octagonal bar with planar facets 76 intersecting at 45°. The magnetic member 68g is formed as an open jaw with a complementary recess for engagement with the facets of the magnetic member 42g.

10084] As may be seen from Figures 20 to 22, the auxiliary frame 50g may be rotated at 45° increments relative to the main frame 12g with a stable position provided at each increment. The auxiliary frame may thus be positioned over a 90° range as illustrated, or beyond to 135° or 180° if the design of frame permits.

10085] A similar arrangement can be obtained in a manner similar to Figure 19, as shown in Figure 23 with appropriate shaping of the temple region 28h. In this arrangement, facets 76h are formed at the required orientation, e, g. 45°, 60° or irregular shapes to provide stable positions for the auxiliary frame SOh on the primary frame 12h.

[00861 In each of the above embodiments, planar surfaces or facets have been provided to introduce stability to the arrangement of primary and auxiliary lenses. It will be appreciated that stability may be introduced by utilising other arrangements, including pins and recesses or other inter-engaging formations with the retention provided by the interaction of the magnetic members. In some situations where the auxiliary frame is small and light, the magnetic retention over a large area, such as that shown in Figures IS and 20 may be sufficient to maintain the auxiliary frame in a pair of positions provided the configuration of the frames permits relative rotation. It is believed however that the provision of co-operating planar surfaces enhances the retention in preferred orientations.

[0087J Each of the above embodiments has also illustrated the location of the magnetic members at the temple regions. This location is preferred to provide inherent stability to the auxiliary frames when mounted. However, if preferred, the configuration of magnetic members and/or frame structure may be incorporated in the bridge 18 to provide a central mounting location where the configuration of frame permits. In this embodiment shown in Figures 24, 25 and 26, the primary frame 12i has a second bridge 118i above the bridge 18i. The second bridge 118i has a magnetic insert 42i incorporated in the upper bridge 118i or alternatively may be formed of magnetic material with a cross section to provide magnetic insert 42i. The bridge 56i of the auxiliary frame 50i carries a rearwardly directed magnetic member 68i that engages either the forwardly directed face 44i or upwardly directed face 46i of the magnetic member 42i.

Again, a pair of stable surfaces are provided to maintain the auxiliary frame 50i in either of the preferred positions.

100881 Other configurations as illustrated with respect to the temples may be incorporated in a similar manner into the bridges.

[0089) For example, as shown in Figure 27, the upper bridge 118j may be trapezoidal and an L-shaped bracket 120 secured to the bridge 56j of the auxiliary frame 50j. Each leg of the bracket 120 includes a magnetic member 68j that wilt engage the upper bridge 118j in one of two positions. The upper bridge 118j may either be magnetic or carry magnetic insert 42j.

100901 As shown in Figure 27, the insert 42k extends through the upper bridge between upper and lower surfaces and so is operable to engage one of the members 68k in each position to retain the auxiliary lens.

[0091] Similarly, in Figure 28, the upper bridge 118k is formed as a part cylindrical shell with a magnetic insert 42k within the shell. A complementary bracket 120k is secured to the auxiliary frame 50k and carries a magnetic member 68k. This permits the auxiliary frame to be slid between different positions on the upper bridge I l 8k.

[0092) As a further alternative, as shown in Figure 29, the bracket 120m is formed as a bell crank with legs at a 135'included angle. Each of the legs supports a magnetic member 68m that engages upper bridge 118. The auxiliary frame 50m may thus be tipped between a pair of positions and held in each by action of the magnetic members 68m. The bridge 118m may be magnetic or may carry a magnetic insert 42m to co-operate with the magnetic members 68m.

[0093) In each of the embodiments of Figures 27 to 29, the auxiliary lens is held in its operative position by engaging the underside of the upper bridge member 118. As shown, in Figure 30 and 3', the auxiliary frame 50n may be provided with an overhanging lip 130 that carries a pair of magnetic inserts 68n. The lip 130 is positioned to engage the upper surface of the upper bridge 118n to hold the auxiliary lens in the operative position.

[00941 The auxiliary lens may then be positioned with the lip 130 behind the upper bridge 118n to hold the auxiliary lens in the alternative position clear of the optical axis.

[00951 As a further alternative as shown in Figure 32, the upper bridge 118n is circular with insert 42n passing through the diameter. The bracket 120n is curved and carries a pair of inserts 68n that allow the auxiliary lens 50n to rotate between a pair of positions.

{0096} In each of the above embodiments, the magnetic connection between the auxiliary frame 50 and the primary 12 is used to accommodate the relative movement between those components. In a further set of embodiments shown in Figures 33 through 46, an alternative arrangement is utilised in which the construction of the auxiliary frame accommodates the relative movement.

[00971 Referring therefore to Figure 33, the eyeglasses I Op are provided with a main frame 12p with lens openings 14p and 16p respectively. A bridge 18p connects the frames defining the lens openings and side arms 24p extend rearwardly from the temple region of the primary frame 12p.

[0098] The auxiliary frame 50p similarly has a pair of lens opening 52p, s4p interconnected by a bridge 56p. The lens opening 52p, 54p are defined by the main frame member 64p.

[0099] In order to secure the auxiliary frame 50p to the main frame 12p, a sub frame 130 is utilised. The sub frame 130, which is best seen in Figure 34, has a pair of arms 132, 134 projecting outwardly from a bridge member 136. The arms 132, 134 conform to the shape of a portion of the upper frame member 30p and each terminates in a hinge for connection to the auxiliary frame 50p.

[001001 The arm 132 terminates in a pin 138 that is received within a tubular sleeve 140 secured to the main frame 64p of the auxiliary lenses 50p. The arm 134 terminates in a threaded boss 142 that is aligned with a sleeve 144 secured to the main frame 63p. A bolt 148 passes through a spring 146 and the sleeve 144 and is retained in the bush 142. The end faces of the bush 144 and sleeve 142 are contoured to provide a pair of detents, each of which holds the frame 50p in a stable position. Thus, the auxiliary frame 50p may pivot relative to the sub frame 130 and be retained in one of a pair of stable positions.

[00101] The bridge member 136 has a pair of magnets 150 projecting downwardly below the bridge member 136. The magnets 150 are received in a pair of sockets 152 formed in the bridge 18p. The sockets 152 pass through the bridge member as can be seen in Figure 35 and the bridge member 18p is made from a magnetic material. The magnets 150 thus retain the bridge member 136 on the bridge 18p to secure the sub frame 130 on the main frame I Op.

[00102 In operation therefore, the sub frame 130 may be secured to the bridge 18p with the auxiliary frame 50p projecting upwardly as shown in Figure 33. In this position, the auxiliary lenses 52p, 54p are out of the line of vision of the user and are held in a stable position. When the shade provided by the auxiliary lens is required, the auxiliary frame 50p is rotated relative to the sub frame 130 to cause the lenses 52p, 54p to overlie the main lenses 14p, 16p. The auxiliary frame 50p is maintained in a stable position relative to the main frame to provide the shade [00103] In the embodiments shown in Figures 34 and 35, the sockets 152 pass through the bridge 18p. Alternatively, as shown in Figures 36 and 37, the sockets 152 do not pass through the bridge 18p to provide a solid base to retain the magnet. The magnets 150 are received in the sockets 152.

[00104] In the embodiment of Figure 36, the magnets are a square cross section but as shown in Figures 38 and 39 and Figures 40, and 41 the magnets may be an alternate cross section such as circular, as shown in those Figures.

[00105] Where the material of the bridge 18p is not magnetic, attraction between the sub frame 130 and the bridge 18p may be obtained by the insertion of magnets 154 at the lower end of the sockets 152. The magnets 150 thus engage the magnets 154 to retain the sub frame on the bridge. In the arrangement shown in Figures 42 and 43, the magnets 150 and sockets 152 are square in cross section whereas as shown in Figures 44 and 45, the magnets are circular in cross section.

[00106] In the above embodiments, a pair of magnets 152 have been utilised but as shown in Figures 46 and 47 a single magnet may be utilised. In this case, the bridge 18p is formed from magnetic material and has a socket 152 formed centrally in the upper surface. A square section magnet 150 depends from the bridge member 136 to secure the auxiliary frame 50p to the main frame.

[00107 In each of the above embodiments the sub frame 130 permits the pivotal movement of the auxiliary frame between the first position in which the lenses are shaded and a second position in which the auxiliary lenses are maintained out of the line of vision.

1001081 It will also be appreciated that the arms 132, 134 may extend laterally outwardly from their connection to the auxiliary frame and be secured magnetically at the temples. However, the provision of a unitary sub frame is believed to be more convenient for the user.

[001091 Further embodiments of eyeglasses are shown in Figures 48 to 59 in which a hinge arrangement is located at a temple portion of the frames.

100110l Referring therefore to Figure 48, a pair of spectacles 210 includes a pair of primary lenses located within a frame 216. The frame 216 includes a pair of lens rims 218 interconnected by a bridge 220. The frame 216 also includes hinge pedestals 222 that are connected to temples 224 by a hinge pin 226. The temples 224 extend rearwardly along the sides of the users head and secure the spectacles in a well known manner.

[00111] A pair of housings 228 are provided on the frame 216 adjacent to the temples 224.

As shown in Figure 50, the housings 228 are located behind the pedestals 222 so as not to be seen from the front. The housing 228 is shown in greater detail in Figure 54 and includes an annular collar 230 that encompasses a magnet 232. The magnet 32 has one of its surfaces 234 exposed and a flange 236 on the collar 230 extends about the periphery of the magnet 232.

[00112] An auxiliary lens assembly 240 similarly comprises a pair of auxiliary lenses 242, 244 contained within a frame 246. The frame 246 includes a pair of wings 248 that project upwardly in the temple regions of the frames 246. A pair of arms 250 are secured to the wings 248 and extend rearwardly from the frame 246. As again, can be best seen in Figure 54. each of the arms 250 extends from the wing 248 to the housing 228 and has an elbow indicated at 252 intermediate its ends. The distal end of the arm 250 remote from the wing 248 has a housing 254 with a recess 256 to accommodate a second magnet 258. A lower face 260 of the housing 254 abuts the flange 236 when the magnets 258,232 are in engagement.

[00113] The arm 250 is secured to the wing 248 through a hinge 262 shown in Figure 55. The hinge 262 includes a slot 264 formed at one end of the arm 250. A hinge body 266 formed at the end of the wing 248 is located in the slot 264 and secured for pivotal movement by a hinge pin 268. The hinge body 266 has a pair of recesses 270, 272 that is shaped to receive the curved end of a pin 274. The pin 274 is slidable in a bore 276 in the arm 250 and biased by a spring 278 into engagement with the hinge body 266. The pin 274 thus provides a detent by co-operation with the recesses 270,272 that biases the hinge to one of two positions.

1001141 In use, the auxiliary lens assembly is attached to the spectacles 246 by aligning the magnets 258 and 232. The magnets provide a retaining force to hold the auxiliary lens assembly 246 on the spectacles 210. In the position shown in solid lines of Figure 54, the auxiliary lenses 242, 244 are positioned to cover the primary lenses 212, 214 respectively and therefore provide additional protection to the user. When the protection is no longer needed, the auxiliary lens assembly 246 may be rotated relative to the arm 250 about the hinge 262.

[00115] As the auxiliary lens assembly 246 is rotated, the pin 274 is moved against the bias of the spring 278 and out of the recess 270. It then assists the continued rotation by entering into the recess 272 to hold the auxiliary lens assembly 246 in the position shown in chain dot lines in Figure 54. During this rotation, a couple is applied to the arm 250 which is resisted by the retaining forces provided by the magnets 258,232. The resistance to movement provided by the detent in the hinge 262 is less than the retaining force provided between the magnets 258, 232 so that the arm 250 remains in a stable position.

(001161 The stability of the arm is enhanced by the abutment between the flange 236 and the lower face of the housing 254. The radial extent of the flange and face increases the resistance to separation of the magnets 258,232 as a couple is applied to the arm 250. The inclined flanks of the flange and face also provide radial location for the arm 250 relative to the housing 228 to resist shear forces between the magnet 58 and 232. Accordingly, a stable attachment between the auxiliary lens assembly 246 and the spectacles 210 is obtained. It will however be appreciated that where sufficient magnetic force is provided, the provision of a flange is not essential, and, where a flange is used is may be flush with the magnets rather than providing lateral location.

[00117] As shown in Figure 56, in which like reference numerals will be used to denote like components with a suffix'a'added for clarity, an alternative configuration of housing 228a and housing 254a may be utilised. In the embodiments shown in Figure 56, the magnet 232a, 258a are encompassed by the flange 236a and the face 260a respectively. The flange 236a and face 260a are planar with an annular upstanding ridge 280 provided on the flange 236a. A corresponding recess 282 is formed in the face 260a and the inter-engagement of the ridge 280 and recess 282 provides lateral location for the two housings but also provides a mechanical interference against tipping of the arm 250a during movement of the auxiliary lens assembly.

This further enhances the stability of the connection.

[00118] A similar arrangement is shown in Figure 57 in which like components will be identified by like reference numerals with a suffix b added for clarity. In the embodiment of Figure 57, the magnet 258b projects from the end face of the housing 254b and the magnet 232b is recessed in the housing 228b. Accordingly, lateral displacement between the arm 250b and the housing 228b is inhibited and tipping of the arm 250b relative to the housing is also inhibited due to the mechanical interference between the inter-engagement of the magnet 258b and the walls of the housing 228b.

[00119] In each of the above arrangements, the exposed faces of the magnets 232, 258 are disposed normal to the plane containing the primary lenses 212, 214, i. e. they are generally horizontal when worn. In the embodiments shown in Figure 58, the housing 228c and 254c are disposed such as the exposed faces of the magnets 232c, 258c are parallel to the plane containing the primary lenses 212, 214. Thus the arm 250c depends downwardly behind the pedestal 222c with the magnet 258c facing forwardly to engage the rearwardly directed face of the magnet 232c. As will be appreciated, the flange provided in each housing enhances the stability and, the mechanical interconnection described above with respect to Figures 54,56 and 57 may also be incorporated in this arrangement.

[00120] The arm 250d may also be arranged as shown in Figure 59 to present the housing 254d to the underside of the housing 228d rather than to the top of the housing as shown in the previous embodiments. In this case, the magnet 232d is disposed with its exposed face downwardly directed and the magnet 258d disposed with its exposed face upwardly directed.

The arm 250d extends parallel to the frame of the auxiliary lens assembly 246 with the elbow 252d located beneath the pedestal 222d. Again, the magnets may be arranged to be flush with the surfaces of the housings 254d, 228d or may incorporate the mechanical interaction shown in Figure 54, 56 and 57 and described above.