Spectacles with two-dimensional adjustment

Abstract

A pair of height-adjustable spectacles for accurately accommodating the position of the wearer’s eyes. The pair of height adjustable spectacles (100, Fig. 1) comprises a frame (101, Fig. 1) comprising

Description

The present invention relates to spectacles, particularly to spectacles that provide for position adjustment of the lenses relative to the frame. Background Short-sightedness (myopia) is treated with spectacles. For effective treatment each lens of the spectacles must be directly in front of each cornea of the wearer. Despite this, spectacles are often not fitted correctly to be fully-effective for the wearer. A design of conventional spectacles is often selected by the wearer for visual aesthetic or style and does not accurately accommodate the position of the wearer’s eyes. Myopia typically starts in children aged 6 to 13 and it is important it is treated as soon as possible to prevent it from worsening. However, as children grow the positioning of the lens in relation to the cornea changes and repositioning the lenses is needed such that effective treatment can be continued. Spectacles with two-dimensional adjustment relative to eyes can allow repositioning of the lenses and avoid the need for new spectacles. Vertical and horizontal adjustment of the lenses in relation to the wearers face allows treatment to continue and keeps a tight fit on the face to prevent the lenses moving when worn. There are many examples of mechanisms in the prior art for lateral adjustment of the spacing between the lenses of a pair of spectacles. For example, the nose pads or nose bridge may be adjusted to alter the spacing of each lens from the bridge of a wearer’s nose. However many such mechanisms are unsightly or difficult to adjust accurately. Furthermore, there are fewer attempts to adjust the height of the lenses effectively. In some examples, the angle of the arms of the spectacles can be adjusted. This initially can be used to set the height at which the lenses are supported relative to the wearer’s ear(s). However, this creates stress at the hinge and over time the spectacles will tend to loosen, e.g. sliding further down the wearer’s nose, or else damage the hinge. KR20130010163 discloses continuous arm height adjustment at the frame edge using a screw thread arrangement. KR20130010158 discloses a series of holes along the frame edge at different heights and a protrusion on the end of the arm that can selectively engage a hole at a desired height. At least one embodiment in that document discloses a wing / flange member on the side of the arm that can be fastened to a selected hole using a bolt-like fastener. The mechanisms disclosed in the prior art are unstable and do not provide a robust connection such that the positioning of the lenses does not change without purposeful adjustment. The attachment mechanisms create a significant point of weakness that are easily broken or loosened. It is an aim of the invention to provide spectacles with two-dimensional adjustment that mitigates one or more of the above-mentioned problems. Statements of Invention According to a first aspect of the invention, there is provided a pair of height-adjustable spectacles as recited in appended claim 1. The protrusions may be located along an edge of either or both rim / lens. The protrusions may be located along a side of either or both rim / lens. The protrusions may provide a plurality of connection points for the respective arm, i.e. providing a plurality of height options for attachment of the arms. The protrusions comprise a plurality of discrete protrusions on the first and / or second rim. Said protrusions may be located on the back / rear face of the first and / or second rim. The height of the first arm may be selected / fixed separately from the height of the second arm and vice versa. The protrusions may comprise one or more engagement surface that is upstanding from the rim. The one or more engagement surface may be obliquely angled relative to an upright side of the frame / rim, e.g. being offset from horizontal / vertical. The protrusion may comprise a pair of opposingly and / or obliquely angled engagement surfaces. The engagement surfaces may comprise opposing side walls of the protrusion. The protrusion may be tapered or chevron-like in form. The protrusion may be trapezoidal in form, e.g. in plan. The protrusion may comprise a channel or groove in its upper surface, e.g. facing away from the rim / frame. The groove may extend between the opposing side walls or engagement surfaces. The groove may receive a fastener when assembled. The protrusions may comprise an abutment formation, e.g. a discontinuity or recess. The abutment formation may be located in a side / edge of the protrusion. The abutment formation may face the rim. The abutment formation may be shaped to engage / receive an opposing formation on the arm, e.g. to resist / prevent removal of the arm from the pedestal in a direction away form the rim when engaged. A latching or snap-fit engagement between the arm and protrusion may be provided. This may provide first engagement means. Second engagement means may be provided by a fastener. Tightening of the fastener may prevent disengagement of the first / latching engagement means. The arm may comprise an engagement formation in its end that is arranged to engage the protrusion. The engagement formation may comprise a female formation or recess. The engagement formation may oppose the protrusion and may comprise a profile that matches the profile of the protrusion, e.g. in plan. The recess may be shaped to closely surround the protrusion, e.g. to closely surround or enclose the protrusion in plan. The recess may be tapered , e.g. chevron-like or trapezoidal, in plan / section. The engagement formation may comprise a slit or discontinuity. The engagement formation may comprise opposing halves, e.g. defining opposing halves of the end / section profile of the engagement formation or recess thereof. The engagement formation may be forked or split. The opposing halves of the engagement formation may be tightened by a fastener, e.g. to clamp onto the protrusion. The opposing halves may clamp onto the tapered engagement surface(s) of the protrusion. A fastener may pass through the arm to fasten the engagement formation onto the protrusion. A releasable fastener may be provided. A threaded fastener may be used. The arm, e.g. the engagement formation thereof, may comprise an opening or through-bore to receive the fastener. The fastener may pass through the opposing halves of the engagement formation. The arm, e.g. the engagement formation, may be threaded to receive the fastener or may comprise a threaded nut to receive the fastener. The fastener may be variably tightenable. The fastener may bear on the protrusion, e.g. a top or upper surface thereof. The fastener may be received by the groove of the fastener. The engagement formation may comprise an abutment / engagement formation for cooperation with the opposing abutment formation of the protrusion. The engagement member may be a projection or recess / discontinuity. The engagement member may comprise a projection or lip, which may be profiled or ramped. The engagement member may be provided in one of the opposing halves of the engagement formation profile. The opposing engagement / abutment formations of the arm and protrusion may comprise a latch or snap-fit. The engagement formation of the arm may be resiliently deformable into an engaged or latched condition on the protrusion. Tightening of the fastener may clamp an end of the arm onto the protrusion. The arm may comprise a hinge. The arm may comprise an intermediate member having the engagement formation and a distal arm member that is hingedly attached to the intermediate member. A horizontal adjustment mechanism may be provided for lateral adjustment of the spacing between the rims / frames. The horizontal adjustment mechanism may be across the nose bridge. The horizontal adjustment mechanism may comprise a brow bar. The horizontal adjustment mechanism may comprise a telescoping brow bar. The brow bar may be a hollow box section in form. The horizontal adjustment mechanism may comprise a latch, e.g. mounted within the brow bar. A latch member may be located inside the brow bar. The latch member may engage detents or openings in the brow bar. The latch member may be biased to an engaged condition. The latch member may comprise a lever arm. The latch member may comprise a triangular or ramped engagement formation. The horizontal adjustment mechanism may comprise a spring and a latch located at an end. The latch may hold the spring in compression. The horizontal adjustment mechanism may comprise a spring biasing the telescoping brow bar and / or latch. The spring may bias the brow bar to an extended condition. The telescoping brow bar may comprise a central section and first and second telescoping members on either side thereof. The telescoping members may depend from each end of the central section. The central section may be hollow to receive the telescoping members or vice versa. According to a second aspect of the invention there is provided a pair of spectacles with two-dimensional adjustment comprising: a frame comprising a pair of rims for holding two lenses and a nose bridge for connecting the pair of rims; a first arm depending from a first rim at a first side of the frame and a second arm depending from a second rim at a second side of the frame; a height positioning system for fixing the height of each of the first and second arms relative to its respective rim; and a horizontal adjustment mechanism for adjusting the distance between the pair of rims. Any optional features described in relation to any one aspect may be applied to any other aspect of the invention wherever practicable. Detailed description Practicable embodiments of the invention are described in further detail below with reference to the accompanying drawings, of which: Figure 1 shows a perspective view of a pair of spectacles in accordance with an example of the invention; Figure 2 shows a perspective view of an assembled vertical adjustment mechanism in accordance with an example of the invention; Figure 3 shows an exploded three-dimensional view of a vertical adjustment mechanism in accordance with an example of the invention; Figure 4 shows a further exploded three-dimensional view of the vertical adjustment mechanism of Figure 3; Figure 5 shows a perspective view of a side of a frame in accordance with an example of the invention; Figure 6 shows a perspective view of an intermediate part in accordance with an example of the invention; and Figure 7 shows a cutaway view of a horizontal adjustment mechanism in accordance with an example of the invention. The invention provides a particularly robust and simple arrangement for attaching the arms to the spectacles at different heights relative to the frame. Embodiments of invention provide a pair of spectacles with discrete mechanisms for two-dimensional adjustment of the positioning of the lenses in relation to the eyes of the wearer. Spectacles come in various sizes to fit different face shapes and position the lenses directly in front of each cornea of the wearer. Two-dimensional adjustment of the spectacles allows the lenses to be repositioned as the user grows to maintain lens position and face fit. This is particularly beneficial for children, who regularly undergo phases of growth. The two-dimensional adjustment may also enable a better fit of the spectacles in children or adults for the purpose of correcting myopia. A pair of spectacles according to an example of the present invention is shown schematically in Figure 1 and generally designated 100. The spectacles 100 or glasses comprise a frame 101 comprising a pair of rims 102 for holding two lenses 103 and a bridge 104 in the form of a brow bar for connecting the pair of rims 102. An arm 105 is located at a first side of the frame 101 and another arm 105 located at a second side of the frame 101. The brow bar 104 is rigidly attached to the top of each rim 102 towards each end of the brow bar. There is provided a horizontal adjustment mechanism located at / in the brow bar 104 which alters the distance between the pair of rims 102 and therefore the position of the two lenses 103 in relation to the face. Each rim can be adjusted independently, e.g. relative to a centre of the brow bar 104 or the other rim. To this end, the brow bar 104 comprises telescoping members 106 that support each rim 102. The horizontal / lateral adjustment mechanism will be described in further detail below. There is provided a vertical adjustment mechanism 107 located where the arms 105 attach to the frame 101. The vertical adjustment mechanism allows the selective vertical positioning of the arms 105 in relation to the frame 101 and therefore the position of the two lenses 103 in relation to the face. Conventional adjustable nose pads 108 are provided to adjust the seating of the frame 101 or individual rims 102 on the wearer’s nose, e.g. in response to the horizontal and / or vertical adjustment mechanisms described herein. Vertical adjustment Figure 2 shows a perspective view of a vertical adjustment mechanism 107 which alters the height at which the arms 105 attach to the sides of the frame 101. The adjustment mechanism may therefore be described as a variable height positioning system. The vertical adjustment mechanism 107 comprises a plurality of protrusions 201 spaced along the back of the side of the frame 101 and an intermediate part 202 configured to connect with one or more of the protrusions 201 to provide a secure, hinged connection between the protrusion 201 and an arm 105. The arm 105 depends rearwardly to its distal end which has an ear engagement / seating portion 109. The rim 102 of the frame comprises a widened lateral edge 102a to accommodate the protrusions 201. The lateral edge 102a has a width dimension sufficient to accommodate the protrusions and also the strength to support an arm at any of the selectable height positions provided by the protrusions. The protrusions 201 are shown in greater detail in Figures 3 and 5. Each protrusion 201 comprises an upstanding pedestal formation that extends rearwardly from the rim 102. In other examples the protrusions could depend laterally from the side of the rim, i.e. rather than rearwardly. However, in the present example, the rearwardly extending pedestals are preferred because they are generally hidden behind the rim 102 when viewed from the front. The protrusions 201 have a tapered form when viewed in plan. In this example, the protrusions 201 have opposing side walls 203 that are opposingly angled so as to narrow towards one edge of the pedestal and widen towards the opposing edge. In this example, the side walls 203 narrow inwardly in a direction towards the nose bridge. However the direction of taper could be outwardly, upwardly or downwardly in other examples. The protrusions may be defined as being trapezoidal in plan. The tapered shape of the protrusions provides a firm fit with the intermediate part 202 and / or arm 105 that offers close alignment and is resistant to loading in different directions. A groove, indent or valley 204 extends though the extent of the protrusion 201 inbetween the side walls 203. The groove 204 extends through the entire width of the pedestal in this example but its orientation could be altered according to the direction of the side walls 103. The groove 204 is provided in the top face of the protrusion 201, facing away / rearwardly from the rim 102. The groove 204 is curved in form, i.e. in section, in this example. A discontinuity 205 is provided in the edge of the protrusion 201. The discontinuity 205 extends between the side walls 103 in this example, i.e. in the outer edge of the protrusion. The discontinuity 205 defines a gap, slot or recess in the side of the protrusion 201 that is arranged to receive a projection or lip on the intermediate part 202 as will be described below. The discontinuity 205 is provided adjacent the interface where the protrusion 201 meets the rim 102 surface and may be described as defining an overhang or lip against which a retaining formation of the intermediate part 202 may engage. A series of three protrusions 201 is shown, with each protrusion being vertically above / below the other protrusions. Two or more protrusions 201 could be provided in other examples, e.g. two or four protrusions could be provided. The protrusions are all of the same form. The protrusions are all commonly aligned, e.g. with the taper, groove etc facing in the same direction. In other examples, rather than discrete protrusions, a single elongate protrusion may be defined with repeating formations along its length to the same effect as the plurality of protrusions described herein. The intermediate part 202 is shown in Figures 3, 4 and 6. One end of the intermediate part 202 comprises a female formation in the form of a hollow or recess 206 for engaging one of the protrusions 102. The recess 206 has a cross sectional profile that matches closely the profile of the protrusions 201 in plan. The profile of the recess 206 is best seen in Figure 6 and is tapered or trapezoidal in form. The profile of the recess may comprise any of the shape features defined herein for the protrusions such that the recess matches and closely surrounds the protrusion with a tight fit. The recess 206 surrounds the perimeter of the protrusion, i.e. in plan. Thus the intermediate part can be engaged with any of the protrusions 201 as required to select a desired height at which the intermediate part, and the associated arm 105, meets the rim 102 of the frame. The recess 206 is bifurcated or split into opposing parts by a discontinuity 207 in the form of a slit that opens in the end of the intermediate part 202 facing the rim / protrusion. The slit 207 terminates part way along the intermediate part 202, e.g. at the opposing end of the recess 206. The recess 206 allows the recess to resiliently deform slightly to engage the protrusion 102 profile. This allows the recess to be opened out over the protrusion profile and to be clamped on to the protrusion once in place. The intermediate art comprises an opening 208 for a fastener 209. The opening 208 comprises aligned openings in each of the bifurcated sides of the engagement formation (i.e. recess) 206 such that the fastener 209 can pass through form one side of the recess to the other. The opening 208 on one side of the recess 208 (i.e. the side opposing the insertion direction of the fastener) is threaded to correspond to the fastener thread. In other examples, the opening on that side of the recess could receive a threaded nut or other threaded receiving formation for the fastener. The opening 208 that receives the head of the fastener may be recessed so the head does not protrude beyond the profile of the intermediate member. When the fastener is inserted through the opening 208 it can be tightened to draw the opposing sides of the recess 206 together. This can thereby clamp onto the protrusion 201. It will be appreciated that the fastener 209 has a threaded shank and takes the form of a screw or bolt in this example. However other types of fastener, tensioner or clamp actuator could be used provided it is sufficiently compact to make it viable for use on an arm of a pair of spectacles. The intermediate part 202 is therefore configured to receive a fastener which tightens the connection between the intermediate part 202 and one of the protrusions 201. This provides a secure / rigid mounting for the arm 105. In the example shown, one side of the recess 206 comprises a plain / flat wall and the other side of the slit 207 comprises a profiled wall, e.g. trapezoidal / tapered to match the profile of the protrusion. However the desired profile could be split in other ways. In Figure 6, there is shown an engagement member 209 which takes the form of a lip on one side of the recess in the end of the intermediate member 202. The engagement member 209 is ramped, e.g. as a triangle or isosceles triangle, in profile. The engagement member 209 extends laterally across one side of the recess. The wall of the recess with the engagement member can flex under the resilience of the material from which the intermediate member is made, e.g. a plastics or metal material. As the recess 206 is pushed over the protrusion 201, the wall of the recess 206 can flex to open the recess and allow the engagement formation 209 to ride over the protrusion and into the discontinuity 205 of the protrusion. The resilience of the recess wall means that the engagement formation 209 snap into the discontinuity 205, akin to a latch. Once mounted the engagement formation 209 acts on the discontinuity as an abutment that prevents / resists separation of the intermediate member from the protrusion on which it is mounted. The engagement formation is then clamped into place by the fastener as a secondary retaining mechanism. The engagement formation is releasably connected to the protrusion in that the fastener can be released and the intermediate member can be pulled away from the protrusion. In this event, the angled face of the engagement member and the resilience of the recess wall allows separation of the intermediate member, e.g. such that it can be repositioned on a different protrusion, if required. By having multiple attachment points (protrusions) for the arms along the frame edge the height at which the arms are attached to the frame can be altered, which in turn adjusts the vertical placement of the lenses in relation to the wearer’s eyes. The intermediate member 202 is connected to the remainder of the arm 105 at a hinge 210. Although the intermediate member 202 and arm 105 are shown in an exploded state in Figures 4 and 5, they may be provided as a common arm assembly that may or may not be disconnectable or separable. The hinge 210 comprises a projection on the arm 105 that is received in a slot on the intermediate member 202 and retained by a pin joint, e.g. by a fastener 211 in this example. The fastener or pin head may be received in a depression in a manner similar to the fastener 209. Various hinge designs are possible and could be used in place of the specific hinge arrangement shown. The arms 105 are thus foldable between extended (in-use) and folded (storage) conditions. The hinge could be biased into the extended and / or folded conditions, e.g. once actuated to or beyond a specific angular orientation. Horizontal Adjustment Mechanism Figure 7 shows a cutaway view of a horizontal adjustment mechanism 300 for the rims 102 of the frame 101. The central brow bar 104 is elongate and hollow. The central brow bar 104 is open at each end and receives a telescoping member 106 in each end. The telescoping members 106 can slide in and out from the brow bar 104 to vary the lateral spacing of the respective lens / rim 102 from the centre of the frame or from the other rim. The central brow bar 104 is of box section, e.g. square in section, and the telescoping members are correspondingly shaped to ensure a robust brow bar with minimal play, whilst still allowing length adjustment. The horizontal adjustment mechanism 300 comprises a spring 302 arranged in compression to bias the telescoping member 106 towards an extended condition. Although not shown in the figure, the brow bar 104 comprises an opening in its side and a latching arm / pawl 304 arranged to selectively engage the opening to retain the telescoping member 106 at a defined position along the brow bar 104. A release member 308 takes the form of a resilient arm with a protrusion at its end, which is positioned adjacent / opposing the opening in the brow bar. Thus pressing of the release member 308 disengages the latching arm 304 from the opening 306 and allows the telescoping member to slid in or out of the brow bar 104. In this manner, the length of the telescoping member 106 may be adjusted as desired whilst depressing the release member 308 to select the desired lateral position of the rim 102. When the release member is let go, the latching arm 304 re-engages the opening 306 and the telescoping member 106 is latched in position. This provides a simple and robust adjustment mechanism that does not introduce significant play or freedom of movement in the brow bar and also does not require the use of special tools to make the adjustment. The spring may bias the telescoping arm and / or latching arm in different arrangements. The entire mechanism can be conveniently housed in the brow bar. The spring / latch is sufficiently strong that it can withstand accidental knocks or impacts due to dropping of the spectacles etc. When the latch is released, and there is no external force exerted, the telescoping member 106 may be pushed by the bias of the spring outwardly such that the distance between the two lenses increases. There is a spring, telescoping member and latch located at either end of the central brow bar 104. The centre of the brow bar may comprise a plug or wall to separate the two mechanisms for lateral adjustment of each of the frame / rim positions independently.

Claims

1. A pair of height adjustable spectacles comprising:a frame comprising a pair of rims for holding two lenses and a nose bridge for connecting the pair of rims;a first arm depending from a first rim at a first side of the frame and a second arm depending from a second rim at a second side of the frame;a height positioning system for fixing the height of each of the first and second arms relative to its respective rim, the height positioning system comprising a plurality of protrusions at different heights on each of the first and second rim, wherein the end of each arm comprises a corresponding formation arranged to receive at least one of said protrusions, andwherein the protrusions comprise a plurality of discrete protrusions on the first and / or second rim.

2. Height adjustable spectacles according to claim 1, wherein the protrusions are arranged one above the other to provide a plurality of height-spaced connection points for the respective arm.

3. Height adjustable spectacles according to any preceding claim, wherein the protrusions are located on a rear face of the first and / or second rim.

4. Height adjustable spectacles according to any preceding claim, wherein the protrusions each comprise one or more engagement surface that is upstanding from the rim.

5. Height adjustable spectacles according to claim 4, wherein the one or more engagement surface is obliquely angled relative to an upright side of the rim.

6. Height adjustable spectacles according to claim 4 or 5, wherein the protrusions each comprise a pair of opposingly angled engagement surfaces.

7. Height adjustable spectacles according to any claim 4, 5 or 6, wherein the engagement surfaces each comprise a side wall of the protrusion.

8. Height adjustable spectacles according to any preceding claim, wherein the protrusions are trapezoidal in plan.

9. Height adjustable spectacles according to any preceding claim, wherein the protrusions are each of the same shape.

10. Height adjustable spectacles according to any preceding claim, wherein protrusions on the first rim oppose the orientation of protrusions on the second rim.

11. Height adjustable spectacles according to any preceding claim, wherein the protrusions each comprise a groove in its outer surface, said groove arranged to receive a fastener in use.

12. Height adjustable spectacles according to any preceding claim, wherein the protrusions comprise an abutment formation such as a discontinuity or recess located in an edge of the protrusion, said abutment formation arranged to engage an opposing formation on the arm to resist / prevent removal of the arm from the protrusion in a direction away from the rim when engaged.

13. Height adjustable spectacles according to any preceding claim, wherein the arm is a snap-fit engagement with the protrusion.

14. Height adjustable spectacles according to claim 13, wherein the arm is further clamped onto the protrusion by a fastener such that tightening of the fastener prevents disengagement of the snap-fit engagement.

15. Height adjustable spectacles according to any preceding claim, wherein the arm comprises a female engagement formation or recess in its end that is arranged to receive the protrusion.

16. Height adjustable spectacles according to claim 15, wherein the recess has a cross-sectional profile that matches the profile of the protrusion so as to closely surround the protrusion.

17. Height adjustable spectacles according to claim 15 or 16, wherein the engagement formation comprises a slit so as to define opposing sides thereof.

18. Height adjustable spectacles according to claim 17, wherein the opposing sides of the engagement formation are clamped onto the protrusion by a fastener.

19. Height adjustable spectacles according to claim 18, wherein the fastener passes through the arm and bears on an upper surface of the protrusion.

20. Height adjustable spectacles according to claim 19, wherein the fastener passes through the arm and bears on an upper surface of the protrusion, against a groove therein.

21. Height adjustable spectacles according to any preceding claim, wherein the corresponding formation of the arm comprises an abutment formation for cooperation with an opposing abutment formation of the protrusion.

22. Height adjustable spectacles according to claim 21, wherein the abutment formation and corresponding abutment formation comprise a projection and a gap, slot or recess, wherein the arm is a snap fit on the protrusion by engagement of the projection in the gap, slot or recess.

23. Height adjustable spectacles according to any preceding claim, further comprising a brow bar extending between the rims and a lateral adjustment mechanism for altering the spacing between the rims.CM24. Height adjustable spectacles according to claim 23, wherein the lateral adjustment mechanism comprises a telescoping member depending form the brow bar to vary the length of the brow bar and a sprung latch mechanism within the brow bar for releasably latching the telescoping member relative to the brow bar.

Images