IMPROVEMENTS IN SPECTACLES OR THE LIKE

Abstract: The invention relates to spectacles, goggles, glasses or the like, in which each sidearm (4) is connected to the lens frame (1) by a common mechanism (5) comprising a track arrangement (6a, 6b) and slider arrangement (7a, 7b). The common mechanism provides for controlled manual adjustement, both of the length of the sidearm relative to the lens frame, and of the angle of inclination of the lens frame relative to the sidearm.

Description: IMPROVEMENTS IN SPECTACLES OR THE LIKE The present invention relates to spectacles, glasses, goggles, eyeshields or the like, of the type including sidearms which engage the wearer's ears, and referred to generically as spectacles in the following description and appended claims. Within the industrial market (and also leisure market) there are a number of spectacles available which offer the ability to adjust the angle of the sidearms relative to the front face or lens arrangement of the spectacle in a generally vertical direction. This effectively changes the angle of inclination or tilt of the front face relative to the wearer, giving greater or lesser protection around the forehead or cheek area of the wearer. This angular adjustment may be achieved by a friction or "click-stop" mechanism whereby the angle can readily set to a selected one of a number of inclined positions. Another common feature is the ability to adjust the length of the sidearms. This temple adjustment enables the spectacles to be "fitted" to the wearer's head/face, thus increasing the comfort and protection offered. Some mechanisms enable the length to be fixed semi-permanently by means of, for example a screw, whereas others use a "click stop" mechanism whereby the length can readily be set to a selected one of a number of positions. A number of spectacle designs have incorporated sidearms which are adjustable both in angular inclination and length. For example, Applicants' safety spectacles identified by the trade mark "Vision" incorporate both of these adjustments. Examples of spectacles incorporating both such adjustments are also disclosed in US-A-4,01 7, 1 65, 4,544,245 and 2,797,61 7. However, the angle and length adjustments have, until now, required separate adjustment mechanisms. It is an object of the present invention to provide an improved spectacle or the like, for example a safety spectacle, incorporating both sidearm length and angle adjustment. According to the present invention, there is provided a spectacle or the like in which both the angle and length adjustments of each sidearm are combined into a single mechanism. According to one aspect of the invention, there is provided a spectacle or the like including a lens arrangement intended to be located in front of the eyes of a wearer, and sidearms connected to the lens arrangement for cooperation with the wearer's ears to hold the spectacle in position on the wearer's head, wherein each sidearm is connected to the lens arrangement by a common mechanism which provides for controlled adjustment, both of the length of the sidearm relative to the lens arrangement, and of the angle of inclination of the lens arrangement relative to the sidearm. In one embodiment, the single mechanism associated with each sidearm includes a track or rail arrangement and a carriage or slider arrangement, one arrangement being connected to the associated sidearm, and the other arrangement being connected to the lens arrangement. The slider and track arrangements have a first mode of relative movement in which the slider arrangement is bodily movable along the track arrangement to adjust the length of the sidearm relative to the lens arrangement, and a second mode of movement in which the slider arrangement is movable relative to the track arrangement to adjust the angular inclination of the lens arrangement relative to the sidearm. The slider arrangement may include a pair of carriages or sliders which are so interconnected that, in said first mode, joint movement of the sliders along the track arrangement is effective to produce lengthwise adjustment of the sidearms, whilst, in said second mode, relative movement between the sliders is effective to adjust the angular inclination of the lens arrangement. The track arrangement of each adjustment mechanism may include a pair of linear, parallel, superimposed tracks, with the sliders being similarly superimposed, slidably displaceable one along each track, and being interconnected by a linkage. The pair of tracks may, for example, be attached to the lens arrangement at one side thereof, whilst the pair of sliders and the associated linkage may be attached to or form part of the sidearm. Manually pulling or pushing the sidearm relative to the lens arrangement causes the pair of sliders to be displaced in unison along the pair of tracks, thus adjusting the length of the sidearm. Manually rocking the sidearm up or down relative to the lens arrangement causes the sliders to be differentially displaced along their tracks by their interconnecting linkage, thus adjusting the angular inclination of the sidearm relative to the lens arrangement. The sliders are arranged to frictionally cooperate with their associated tracks so as to resist unintentional movement therebetween, but to permit intentional movement therebetween by the wearer during lengthwise and/or angular adjustment. For example, each slider and associated track may be coupled together via a spring-loaded ratchet arrangement providing incremental or "click-stop" adjustment between the slider and track. The carriage arrangement, for example the pair of sliders and their interconnecting linkage, may be molded integrally with the associated sidearm, from a resilient synthetic plastics material. Each sidearm may be molded to a generally "wishbone" or "Y" configuration, with the sliders molded to the free ends of the bifurcated arm portions corresponding to the upper limbs of the "Y" , and the free end of the arm portion corresponding to the lower limb of the "Y" forming the ear- engaging portion of the sidearm. One of the bifurcated arm portions is resilient, and the other is hinged to its associated slider, so as to form a linkage interconnecting the two sliders in a manner which converts translational movement between the sliders into angular adjustment of the sidearm relative to the lens arrangement. The track arrangement may be molded integrally with, or otherwise attached to, the lens arrangement, or may be hingedly connected thereto to allow the sidearm to be folded against the back of the lens arrangement for compact storage when the spectacle is not in use. In order that the invention may be more readily understood, one embodiment will now be described with reference to the accompanying drawings, in which:- Fig. 1 is a side view of a safety spectacle embodying the invention; Fig. 2 is a fragmentary perspective view of the safety spectacle shown in Fig. 1 ; Fig. 3 is a side view of the sidearm shown in Figs. 1 and 2; Figs. 4 to 6 are sections on the lines B-B to D-D in Fig. 3; Fig. 7 is an enlarged fragmentary side view of the sliders shown in Fig. 3; Fig.8 is an end view of the sliders in the direction of the arrow "A" in Fig. 7; Fig. 9 is a plan view of the sliders in the direction of the arrow "B" in Fig. 7; Fig. 1 0 is a side view of one of the side shields of the spectacle shown in Figs. 1 and 2; Fig. 1 1 is a section on the line A-A in Fig. 1 0; Fig. 1 2 is a fragmentary side view, partially broken away, of the track arrangement shown in Fig.1 1 ; and Fig. 1 3 is a plan view of one of the side shields. As shown in Figs. 1 and 2, the safety spectacle incorporates a front face or lens arrangement comprising a frame 1 fitted with a pair of lenses 2. Side shields 3, which may be transparent, are attached to the left-and right- hand sides of the frame 1 . The frame may be formed from a metal or a synthetic plastics material, for example molded from a clear, coloured or translucent plastics such as nylon. The lenses may be formed from toughened glass, or a transparent plastics material such as a polycarbonate, or CR39 (an allyl diglycol carbonate resin). A sidearm 4 is connected one to each side shield 3 by a mechanism 5 which permits the sidearm to be adjusted both in length and angular inclination relative to the frame. Additionally, the side shields may be hinged to the frame to allow the side shields and sidearms to be folded transversely behind the frame for compact storage when not in use. As will be apparent from Figs. 1 and 1 0 to 1 2, each side frame 3 carries a track arrangement comprising a pair of parallel upper and lower L-section rails or tracks 6a having opposed inner faces formed with ratchet teeth 6b. Outwardly opening longitudinally extending channels 6c are formed between the side shield 3 and rails 6a, each channel being closed by an end wall 6d at its forward end adjacent the frame 1 , and being provided with a stop 6e adjacent its other, open, rearward end. As shown in Figs. 1 to 3, each sidearm 4 is bifurcated into a generally "wishbone" or "Y" configuration. The arm portion 4a, corresponding to the base limb of the "Y", forms the temple end or ear-engaging end of the sidearm. The upper bifurcated arm portion 4b is relatively deep and relatively rigid, having a generally "L" shaped cross-section as shown in Fig. 4, and is connected by an integral hinge 4c to an upper carriage or slider 7a. The lower bifurcated arm portion 4d is relatively thin and resilient, having a generally flat cross-section as shown in Fig. 5, and is connected directly to a lower carriage or slider 7b. The upper slider 7a includes a lower transverse wall 7c (Figs. 3, 7 and 8) formed with longitudinally distributed, upwardly projecting ratchet teeth 7d, which cooperate with the downwardly projecting ratchet teeth 6b of the upper track 6a. As also shown in Fig. 8, lower wall 7c is connected by an outer side wall 7e to an upper transverse wall 7f having a slot 7g (Fig. 9), and the striplike portion 7h of the wall 7f, which is free to flex intermediate the ends of the slot, has a bowed configuration as shown in Fig. 7. The upper slider 7a thus defines a longitudinally extending L-section channel 7] so as to accommodate and interfit with the L-section of the upper rail 6a shown in Fig. 1 1 . In this condition, the bowed, strip like portion 7h is engaged in the channel 6c, and resiliently engages the base of the channel 6c, resiliently drawing the slider ratchet teeth 7d into engagement with the rail ratchet teeth 6b . The configuration of the lower slider 7b, and the manner in which it slidably cooperates with the lower rail 6a, is basically similar to that just described in relation to the upper slider 7a, and will therefore not be described in detail. Each sidearm 4 and its associated sliders 7a, 7b are preferably formed in one piece, for example molded for a relatively resilient synthetic plastics material, such as nylon, which may be coloured, translucent, or transparent. The rails 6a are, likewise, preferably formed integrally with their associated side shields 3, for example molded from a relatively rigid transparent synthetic plastics material such as a polycarbonate. To assemble each sidearm 4 to its side shield, the sliders 7a, 7b are slid onto the longitudinal free ends of the associated rails 6a (the upper ends as viewed in Figs. 10 and 1 2. The bowed spring portion 7h of each slider resiliently rides over and past the stop 6e (Fig. 1 2), this being facilitated by the camming action between the curved leading edges or ramps of the stop and bowed spring portion. Once the spring portion 7h has advanced past the stop 6e, the shoulders at the trailing edges of the stop and spring portion will cooperate to prevent the slider from unintentionally sliding back of the rails. In this assembled condition as shown in Figs. 1 and 2, the ratchet teeth of the sliders and rails are resiliently urged into engagement by bowed spring portions 7h which press on the bases of the associated rail channels 6c, thus preventing unintentional sliding movement between the sliders and rails. The spring portions also cooperate with the base and tapered sides of the rail channels 6c to locate the sidearms 4 laterally relative to the frame 1 with the minimum of play. In use, when a wearer wishes to adjust the length of the sidearms 4 relative to the frame 1 , it is merely necessary to manually pull or push the sidearms longitudinally relative to the frame, with a force sufficient to overcome the bias of the bowed spring portions 7h,. This will cause both sliders to slide in unison, with a ratchet action, along their associated rails, incrementally, to the required new position. The sliders will remain in that position, due to the resilient interengagement of the ratchet teeth, until intentionally readjusted by the wearer. When the wearer wishes to adjust the angular inclination of the sidearms 4 relative to the frame 1 , each sidearm is manually tilted upwardly or downwardly relative to the frame. This action, coupled with flexing of the hinge 4c in the upper arm portion 4b, and bowing of the lower arm portion 4d, causes the sliders to slide relative to each other along their associated rails with a ratchet action. When the adjusting force is removed, the sliders will remain in their relatively displaced positions due to the resilient interengagement of the ratchet teeth, until further adjustment is deliberately effected. From the foregoing, it will be apparent that adjustment both of the length and angular inclination of each sidearm relative to the frame is accommodated by a common mechanism, i.,e. the pair of cooperating sliders and rails, and the hinged/resilient bifurcated arm portions interconnecting the pair of sliders. The mechanism incudes a minimum of components, and the various components may conveniently be formed as moldings. This reduces the number of components required, and simplifies the components, so that fewer molding tools are required, thus reducing the capital outlay. The assembly is simplified, and becomes quicker and cheaper. No screws or rivets are required to hold the sidearm on the side shield or frame. This is effected by the spring mechanism molded integrally with each sidearm, comprising the bowed spring portion 7h of each slider. The spring action enables the correction pressure to be exerted to resiliently hold the sets of ratchet teeth together. The linkage interconnecting the sliders 7a, 7b of each pair, comprising the bifurcated hinged upper arm portion 4b of the sidearm, and the bifurcated resilient lower arm portion 4d, translates angular inclination or rocking movement into relative opposed displacement between the sliders without disengaging or otherwise interfering with the intermeshing of the sets of ratchet teeth. It will be understood that various modifications may be made without departing from the scope of the present invention. For example, the invention may be applied to various types of eye shields, glasses, etc. and is not limited to safety spectacles. The spectacles may be for other purposes, such as leisure, for example sunglasses, or for use with prescription lenses. The spectacle, or the like may include a one-piece lens in the form of a single transversely extending shield or visor, instead of a pair of individual lenses as shown, and the frame, if provided, may take the form of a brow bar or bow. When the frame, or lens arrangement, is formed from a plastics material, the adjustment mechanism, for example the track or slider arrangement may be attached directly to, or molded integrally with the frame, or lens arrangement. The side shields, if provided, may also be attached or molded directly to the lens arrangement. The individual length/angle adjustment mechanisms may be reversed, for example, the track arrangement may be attached to or form part of the sidearm, and the slider arrangement may be attached to or form part of the side shield if provided, or the frame or lens arrangement. When the sidearms or side shields are hingedly connected to the frame or lens arrangement, then the hinge mechanisms may be incorporated in the length/angle adjustment mechanisms. The length/angle adjustment mechanism associated with each sidearm may take a variety of different forms. For example, the ratchet teeth may be replaced by friction surfaces or brake systems, the frictional resistance of which may be simply overcome by applying a manual adjusting force to the sidearms. Alternatively, the mechanism may incorporate a resilient detent or lever control which is depressed or otherwise activated when it is required to free the mechanism to adjust the inclination and/or length of the sidearm. The pair of sliders shown in the illustrated embodiment could be replaced by a single slider located between and engaging the ratchet teeth or equivalent of both rails of the track arrangement. In this modification, the slider may be provided with a curved surface or surfaces, for example a cylindrical surface or part-cylindrical surfaces, provided with ratchet teeth or equivalent, which cooperate with the rails so that the slider is rotatable, and bodily displaceable, relative to the rails, for angular and lengthwise adjustment respectively. Alternatively, the pair of rails in the illustrated embodiment could be replaced by a single rail, with the pair of sliders being mounted on the single rail in spaced apart relation. The linkage interconnecting the two sliders would be configured so that the two sliders more in unison during lengthwise adjustment, but move relative to each other to accommodate and control angular adjustment. The sliders may cooperate with a common surface of the rail which is provided with ratchet teeth or equivalent, or the rail may be provided with upper and lower surfaces provided with ratchet teeth or equivalent, each surface cooperating with one of the sliders. Each adjustment mechanism may be so designed that the force required to displace one slider is greater than that required to displace the other slider. Thus, during angular adjustment, only displacement of the latter slider will normally occur. Thus, the sidearm will, in effect, rock about the former slider, thereby maintaining the length adjustment effectively unaltered during angular adjustment. The sidearms may be connected directly to the frame or lens arrangement, and may be associated with optional side shields releasably attachable to the sidearms, frame or lens arrangement. The pair of lenses, or individual lens may be interchangeably attached to the frame or equivalent. For example, the frame shown in Fig. 1 may be split in a horizontal transverse plane between the upper and lower rails, the upper and lower frame parts being held assembled by the sidearms when attached to the rails. Alternatively, the frame may be split in a horizontal transverse plane passing through, i.e. splitting, one of the rails of each pair, so that the associated sliders when assembled to the split rails, will retain the split rails, and therefore the frame, in its assembled condition. The spring bias arrangement described with reference to the sliders, is of particular advantage, since it enables the correct pressure to be exerted to hold the ratchet teeth together. This arrangement may be applied to other forms of eye protection, such as goggles. In this event, an adjusting mechanism as herein described may be incorporated in one or both ends of the head band or strap.

Claims: CLAIMS 1 . A spectacle or the like, including a lens arrangement intended to be located in front of the eyes of a wearer, and sidearms connected to the lens arrangement for cooperation with the wearer's ears to hold the spectacle or the like in position on the wearer's head, wherein each sidearm is connected to the lens arrangement by a common mechanism which provides for controlled adjustment, both of the length of the sidearm relative to the lens arrangement, and of the angle of inclination of the lens arrangement relative to the sidearm. 2. A spectacle as claimed in claim 1 , wherein the single adjustment mechanism associated with each sidearm includes a first, track or rail arrangement and a second, carriage or slider arrangement, one of said first and second arrangements being connected to the associated sidearm, and the other of said first and second arrangements being connected to the lens arrangement. 3. A spectacle as claimed in claim 2, wherein said first and second arrangements of each adjustment mechanism have a first mode of relative movement in which the second arrangement is bodily movable along the associated first arrangement to adjust the length of the sidearm relative to the lens arrangement, and a second mode of movement in which the second arrangement is movable relative to the associated first arrangement to adjust the angular inclination of the lens arrangement relative to the sidearm. 4. A spectacle as claimed in claim 3, wherein the second arrangement of each adjustment mechanism includes a pair of carriages or sliders which are so interconnected that, in said first mode, joint movement of the carriages or sliders along the associated first arrangement is effective to produce lengthwise adjustment of the sidearms, whilst, in said second mode, relative movement between the carriages or sliders is effective to adjust the angular inclination of the lens arrangement. 5. A spectacle as claimed in claim 4, wherein the first arrangement of each adjustment mechanism includes a pair of linear, parallel, superimposed tracks, and the second arrangement includes a pair of similarly superimposed sliders, slidably displaceable one along each track, and being interconnected by a linkage. 6. A spectacle as claimed in claim 5, wherein the pair of tracks of the first arrangement of each adjustment mechanism is attached to the lens arrangement at one side thereof, whilst the pair of sliders and the associated linkage of the second arrangement are attached to or form part of the associated sidearm. 7. A spectacle as claimed in claim 5 or 6, wherein the sliders of each second arrangement are arranged to frictionally cooperate with the tracks of the associated first arrangement so as to resist unintentional movement therebetween, but to permit intentional movement therebetween by the wearer during lengthwise and/or angular manual adjustment. 8. A spectacle as claimed in claim 7, wherein each slider and associated track are coupled together via a spring-loaded ratchet arrangement providing incremental adjustment between the slider and track. 9. A spectacle as claimed in any of claims 5 to 8, wherein the sliders and associated interconnecting linkage of each second arrangement are molded integrally with the associated sidearm, from a resilient synthetic plastics material. 10. A spectacle as claimed in claim 9, wherein each sidearm is molded to a generally "Y" configuration, with the associated sliders molded to the free ends of the bifurcated arm portions corresponding to the upper limbs of the "Y" , and the free end of the arm portion corresponding to the lower limb of the "Y" forming the ear-engaging portion of the sidearm. 1 1 . A spectacle as claimed in claim 1 0, wherein one of the bifurcated arm portions of each sidearm is resilient, and the other is hinged to its associated slider, so as to form a linkage interconnecting the two sliders in a manner which converts translational movement between the sliders into angular adjustment of the sidearm relative to the lens arrangement. 1 2. A spectacle as claimed in claims 2 to 1 1 , wherein each said first arrangement is hingedly connected to the lens arrangement to allow the associated sidearm to be folded against the back of the lens arrangement for compact storage when the spectacle is not in use.

Inventors: BULL JOHN, BULL, JOHN
Applicants: BULL JOHN, ILES OPTICAL LTD, BULL, JOHN, ILES OPTICAL LTD.
Application year: 1998
Main classification: G02C5
IPC codes: G02C5