Abstract:
Eyewear is provided, namely, sunglasses with an integral securing mechanism that enables the lenses to be removed and replaced as necessary. Each of the lenses may retained within the frame of the eyewear/sunglass device as by corresponding channels or recesses formed on each corresponding side of the sunglass frame. For separate lenses, a securing mechanism is provided for securing each of the lenses. In a mono lens configuration, a single securing mechanism may be used to secure both lenses. A securing mechanism is placed in a locked position to hold the lens(es) in place during use. The securing mechanism is placed in an unlocked position by sliding or shifting the securing mechanism, enabling removal of the lens(es). Various constructions can be adopted for maintaining the securing mechanism in the locked position, such as by frictional force, magnetic force, or combinations thereof.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims the benefit of U.S. Provisional Application Ser. No. 61/809,803, filed Apr. 8, 2013, the entirety of which is incorporated herein by this reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to eyewear with removable lenses facilitated by a securing mechanism that enables the lenses to be secured during use, and to be released in order to remove and replace the lenses. 
       BACKGROUND OF THE INVENTION 
       [0003]    While embodiments described herein are in the context of sunglasses, it should be appreciated that the concepts and structures described herein apply equally to all types of optical eyewear, not just sunglasses. Reference to sunglasses is illustrative and is not intended to be limiting. 
         [0004]    Sunglasses are worn by an increasing number of people. The surge in the wear of sunglasses is due to many factors, including awareness for the need to protect the eyes from damaging sunlight, safety concerns, and also fashion reasons. Accordingly, there has been a proliferation of styles of sunglasses and types of lenses made available to the consuming public. 
         [0005]    One substantial factor in the decision to purchase and wear sunglasses is the cost associated with purchasing a pair of sunglasses that fit the consumer&#39;s particular needs. Sunglasses used for sporting events may require different functional attributes compared to sunglasses used for driving, and sporting and driving sunglasses may have yet further functional requirements different than sunglasses used for casual wear. Accordingly, a consumer may own multiple pairs of sunglasses that adds to the cost of maintaining sunglasses. 
         [0006]    It is also known that sunglasses become damaged from wear over time. The traditional solution for alleviating this problem is to simply purchase a new pair of sunglasses. 
         [0007]    Therefore, there is a need to address the cost associated with a consumer&#39;s need for multiple sunglasses. Further, there is a need to provide a consumer with greater flexibility in terms of the type of lenses available for use based upon the wide variance in reasons why a consumer needs sunglasses. Yet further, there is a need to provide a consumer with a sunglasses construction that is robust, yet may accommodate multiple types of lenses to help alleviate the costs associated with having to own multiple pairs of sunglasses. 
       SUMMARY OF THE INVENTION 
       [0008]    A sunglasses device is provided with an integral securing mechanism that enables the lenses to be removed and replaced as necessary. Each of the lenses may be retained within the frame of the eyewear/sunglasses device as by corresponding retaining channels or recesses formed on each corresponding side of the sunglass frame. For separate lenses, a securing mechanism is provided for securing each of the lenses. In a mono lens configuration, a single securing mechanism may be used to secure both lenses. 
         [0009]    The securing mechanism is placed in a locked position to hold the lens(es) in place during use. The securing mechanism is placed in an unlocked position by sliding or shifting the securing mechanism, enabling removal of the lens(es). Various constructions can be adopted for maintaining the securing mechanism in the locked position, such as by frictional force, magnetic force, or combinations thereof. 
         [0010]    In one preferred embodiment of the invention adapted for use with separate lenses, the sunglasses include a pair of securing mechanisms mounted on the respective end pieces of the sunglasses frame. Each securing mechanism is movable between the locked and unlocked positions. More specifically, a securing mechanism is slid or translated toward a facing surface of the adjacent lens to place the securing mechanism in the locked position. The securing mechanism is slid or translated away from the lens for placement of the mechanism in the unlocked position that allows the lens to be removed from within the retaining groove(s) of the frame. 
         [0011]    Further in accordance with this first preferred embodiment, the securing mechanism is mounted to the corresponding end piece in which the securing mechanism may be moved in a linear, sliding fashion to place the securing mechanism in either the locked or unlocked position. A slot or opening is formed in the end piece, and the securing mechanism is slidable within the slot/opening. Movement of the securing mechanism towards the lens allows the securing mechanism to be placed in the locked position by the mechanism engaging a feature on the lens, while movement of the securing mechanism away from the lens disengages the securing mechanism from the lens for placement in the unlocked position, thereby facilitating removal of the lens. 
         [0012]    In one particular aspect of the first preferred embodiment, the securing mechanism may be provided in the form of a slidable tab that is mounted within the slot of the end piece. The securing mechanism may include a spring-loaded catch that is used to hold the lens in place by movement of the securing mechanism so that the catch engages a protruding hook or extension formed on the exterior edge of the lens that faces the securing mechanism. A retaining spring can be used to urge the securing mechanism to a normally locked or engaged position. Therefore, some amount of force is required to move the securing mechanism to the unlocked position, thereby ensuring the lens does not become inadvertently dislodged from its aligned and mounted position within the frame. 
         [0013]    In another aspect of the invention, the securing mechanism may incorporate other means to engage and hold the lens. Accordingly, in another preferred embodiment, the securing mechanism and the facing surface of the corresponding lens may incorporate a tongue and groove type connection in order to hold the lens in the place during use. 
         [0014]    In yet another preferred embodiment, one end the securing mechanism may be inserted within a complementary shaped gap in the facing surface of the lens in order to secure the lens. 
         [0015]    In yet another embodiment, the securing mechanism slides within a slot formed in the end piece of the ear stem and forms a channel or groove to engage a peripheral edge of the lens. The securing mechanism is shaped such that it may only be moved from a locked position to an unlocked position when the temple or ear stem is in a folded or closed state. In addition, movement of the ear stem to an open or unfolded state will cause the securing mechanism to move to a locked position. 
         [0016]    In yet another preferred embodiment, the securing mechanism may incorporate the use of magnets in order to secure the lens as opposed to a mechanical engagement between the securing mechanism in the lens, or a combination of both mechanical engagement and use of magnets may be used. For the use of magnets according to a preferred embodiment of the invention, the securing mechanism may include a first magnet mounted to a surface of the mechanism. When the mechanism is moved to the locked position, the first magnet is placed into close proximity or contact with a second magnet mounted to the facing edge or surface of the lens. The force of the magnets therefore provides a means to hold the lens in place. 
         [0017]    The securing mechanism can be selectively shaped and sized so that the securing mechanism aesthetically matches the style of the sunglasses. Further, the securing mechanism may be selectively mounted to different portions of the corresponding end piece. For example, the securing mechanism may be mounted along an upper or lower portion of the end piece, or may be more centrally located along the end piece. 
         [0018]    In another embodiment of the invention, instead of using a pair of securing mechanisms, a single securing mechanism can be used with a mono-lens configuration. A mono-lens configuration is one in which the pair of lenses is connected to one another by a bridge piece, thereby resulting in the lenses being a single unit. Accordingly, one securing mechanism can be used to engage one of the lenses, while the other lens may be secured by features formed on the other lens, such as sufficient numbers and spacing of extensions or protuberances received within corresponding retaining channels or recesses of the sunglass frame. 
         [0019]    The construction of the securing mechanism is especially adapted to enable a user to quickly remove a lens, and to replace the removed lens without the need for tools. The capability to remove and replace lenses for sunglasses allows a consumer to use both prescription and nonprescription lenses within the same sunglass frame design. Further, the invention may be adapted for use in full frame designs and “rimless” frame designs, that is, a rim/frame design in which the lower portion of the frame has been removed and the lower portion of the lens is exposed. 
         [0020]    Considering the above features and characteristics of the invention, it can therefore be considered in one aspect sunglasses with removable lenses, comprising: (i) a sunglasses frame including a pair of sunglass frame members for holding respective lenses, a bridge interconnecting the frame members, each of the frame members including respective frame end pieces, and a pair of temples or ear stems hingedly connected to corresponding end pieces; and (ii) a securing mechanism secured to one of the end pieces, said securing mechanism including a portion thereof for engaging a facing surface of a corresponding lens, and said securing mechanism being slidable between a locked position for holding the lens against the frame, and an unlocked position in which the securing mechanism is moved away from the facing surface of the lens. 
         [0021]    In another aspect of the invention, it may also be considered a securing mechanism especially adapted for use with sunglasses in order to secure lenses of the sunglasses to a frame of the sunglasses, said mechanism comprising: (i) a body secured to an end piece of the frame, said body including a portion thereof for engaging a facing surface of a corresponding lens, and said securing mechanism being slidable between a locked position for holding the lens against the frame, and an unlocked position in which the securing mechanism is moved away from the facing surface of the lens; and (ii) an element formed on said body for holding the body against the lens, said element including at least one of a frictional or positional engaging member for engaging the lens, or a magnetic member for magnetically engaging the lens. 
         [0022]    In yet another aspect of the invention, it may also be considered a method of removing and replacing lenses in eyeglasses such as sunglasses, the method comprising: 
         [0023]    (1) providing: 
         [0024]    (i) a frame including a pair of frame members for holding respective lenses, (ii) a bridge interconnecting the frame members, each of the frame members including respective frame end pieces, (iii) a pair of temples hingedly connected to corresponding end pieces, (iv) a securing mechanism secured to one of the end pieces, said securing mechanism including a portion thereof for engaging a facing surface of a corresponding lens, said securing mechanism being slidable between a locked position for holding the lens against the frame, and an unlocked position in which the securing mechanism is moved away from the facing surface of the lens; 
         [0025]    (2) grasping the securing mechanism and sliding the mechanism from the locked to the unlocked position; 
         [0026]    (3) removing the lens from the frame; 
         [0027]    (4) obtaining a replacement lens and placing the lens in engagement with features on the frame for retaining the replacement lens; and 
         [0028]    (5) grasping the securing mechanism and sliding the mechanism from the unlocked to the locked position in order to secure the replacement lens in the frame. 
         [0029]    Other features and advantages of the invention will become apparent with a review of the following detailed description, taken in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]      FIG. 1  is a fragmentary front view of sunglasses showing a securing mechanism mounted to an end piece of the sunglasses; 
           [0031]      FIG. 2A  is an enlarged front view of the securing mechanism of  FIG. 1 ; 
           [0032]      FIG. 2B  is an enlarged vertical cross-sectional view of the securing mechanism of  FIG. 1 , illustrating components of the securing mechanism; 
           [0033]      FIG. 2C  is an enlarged rear view of the securing mechanism of  FIG. 1 ; 
           [0034]      FIG. 2D  is an enlarged rear perspective view of the securing mechanism of  FIG. 1 ; 
           [0035]      FIG. 2E  is an enlarged rear exploded perspective view of the securing mechanism of  FIG. 1 ; 
           [0036]      FIG. 3  is a fragmentary front view of sunglasses showing a securing mechanism in another preferred embodiment of the invention; 
           [0037]      FIG. 4A  is an enlarged front view of the securing mechanism of  FIG. 3 ; 
           [0038]      FIG. 4B  is an enlarged rear view of the securing mechanism of  FIG. 3 , showing the securing mechanism engaged with the facing surface of the corresponding lens; 
           [0039]      FIG. 4C  is an end view of the securing mechanism of  FIG. 3 ; 
           [0040]      FIG. 4D  is an enlarged rear perspective view of the securing mechanism of  FIG. 3 ; 
           [0041]      FIG. 4E  is an enlarged front perspective view of the securing mechanism of  FIG. 3 ; 
           [0042]      FIG. 5  is a fragmentary front view of sunglasses showing a securing mechanism in yet another preferred embodiment of the invention; 
           [0043]      FIG. 5A  is an enlarged fragmentary view of  FIG. 5  showing the portion of the end piece to which the securing mechanism is mounted; 
           [0044]      FIG. 6A  is an enlarged front view of the securing mechanism of  FIG. 5 ; 
           [0045]      FIG. 6B  is a an enlarged plan view of the securing mechanism of  FIG. 5 ; 
           [0046]      FIG. 6C  is an enlarged rear perspective view of the securing mechanism of  FIG. 5 ; 
           [0047]      FIG. 6D  is an exploded enlarged rear perspective view of the securing mechanism of  FIG. 5 ; 
           [0048]      FIG. 7A  is a fragmentary front view of sunglasses with the lens removed, and showing a securing mechanism in yet another preferred embodiment of the invention; 
           [0049]      FIG. 7B  is a plan view of the lens of  FIG. 7A ; 
           [0050]      FIG. 8A  is an enlarged front view of the securing mechanism of  FIG. 7A ; 
           [0051]      FIG. 8B  is an enlarged rear view of the securing mechanism of  FIG. 7A ; 
           [0052]      FIG. 8C  is an end view of the securing mechanism of  FIG. 7A  taken along line C-C of  FIG. 7A , illustrating the securing mechanism mounted within a slot of the end piece; 
           [0053]      FIG. 8D  is a greatly enlarged perspective view of the securing mechanism of  FIG. 7A ; 
           [0054]      FIG. 8E  is a greatly enlarged exploded perspective view of the securing mechanism of  FIG. 7A ; 
           [0055]      FIG. 9A  is an exterior perspective view of a further embodiment of a securing mechanism; 
           [0056]      FIG. 9B  is an interior perspective view of the securing mechanism of  FIG. 9A ; 
           [0057]      FIG. 10  is a top partially exploded view of the securing mechanism of  FIG. 9A ; 
           [0058]      FIG. 11A  is an enlarged interior perspective view of the end piece of the frame of  FIG. 9A  with the lens and securing mechanism removed; 
           [0059]      FIG. 11B  is an enlarged interior perspective view of the end piece of the frame of  FIG. 9A  with the lens removed and the rear securing mechanism tab removed, the securing mechanism in an unlocked position and the lens removed; 
           [0060]      FIG. 12A  is an enlarged exterior perspective view of the frame depicted in  FIG. 9A  with the temple in a closed position, the securing mechanism in an unlocked position and the lens removed from the frame; 
           [0061]      FIG. 12B  is an enlarged exterior perspective view of an end piece of the frame shown in  FIG. 9A  with the temple in a folded position and the securing mechanism in an unlocked position; 
           [0062]      FIG. 12C  is an enlarged exterior perspective view of an end piece of the frame shown in  FIG. 9A  with the temple in a folded position, the securing mechanism in an unlocked position and the lens is removed; 
           [0063]      FIG. 13A  is a top perspective view of the securing mechanism and a lens of the embodiment of  FIG. 9A  in an unlocked state; 
           [0064]      FIG. 13B  is a top perspective view of the securing mechanism and lens of  FIG. 9A  in a locked state. 
       
    
    
     DETAILED DESCRIPTION 
       [0065]    Referring to  FIG. 1 , the invention is illustrated in a first embodiment in which a securing mechanism  30  is used to releasably secure a lens  22  within eyeglasses  10 , such as sunglasses.  FIG. 1  is intended to illustrate a common construction for sunglasses  10 , in which a pair of lenses  22  are held within respective frame portions of the sunglasses  10 . The sunglasses  10  are more particularly shown as including a frame  12  that is used to secure designated portions of the lens  22 . The sunglasses further include other known components, including a bridge  14 , an end piece  18 , and a temple  16  that is interconnected to the frame/end piece by a hinge  20 . The particular construction for the frame  12  may include a full frame design as shown in which the frame  12  supports most of the circumference of the lens  22 . Alternatively, the frame  12  could be “rimless” in which the lower edge or portion  13  of the frame is removed, and the lower edge of the lens  22  being exposed. 
         [0066]    In accordance with the present invention, it is also contemplated that the lens  22  may be of a desired construction such that the lens is easily removed and replaced within the corresponding sunglasses frame  12 . Accordingly,  FIG. 1  illustrates the lens  22  with two extensions or protuberances  23  located at the upper outside corners of the lens. These extensions  23  fit within corresponding retaining grooves or channels (not shown) formed within the frame  12 . These two points of attachment at the location of the extensions  23  combined with engagement of the lens at the securing mechanism  30  provides a robust connection between the lens and the frame  12 . Although  FIG. 1  illustrates two extensions  23 , it is also contemplated that the lens can be configured with additional extensions  23  for placement within corresponding grooves or channels of the frame; or the frame  12  itself could include another arrangement in terms of one or more channels for receiving other designated portions of the lens  22  in order to hold it into place. 
         [0067]    The securing mechanism is mounted to the end piece  18 , such as by a slot or opening  54  formed in the end piece  18 . The securing mechanism  30  includes structure for engaging the slot  54 , enabling the securing mechanism to be slid or translated between a locked and unlocked position. Referring also to  FIGS. 2A-2C , details are shown for the securing mechanism. The front surface or face of the securing mechanism  30  includes features that assist a user in sliding the securing mechanism, such as grips or grooves  34  formed on the body  32  of the mechanism  30 . The structure provided for sliding the mechanism  30  is shown as a mounting rail  36 , which is fitted within the slot  54 . As shown, the mounting rail  36  may include a flange  42  attached to the body  32  of the mechanism  30  by an interconnecting web  43 . Accordingly, a pair of opposing recesses  44  is formed on opposite sides of the web  43  as best shown in  FIG. 2C . The slot  54  is located on the end piece  18  such that the lower edge portion of the end piece  18  resides within the recesses  44 , and the body of the end piece  32  extend below the end piece  18 . Referring to  FIG. 2B , the mechanism  30  may further include a catch  48  that engages a hook or protrusion  56  on the facing surface of the lens  22 , such that when the mechanism  30  is slid to a locked position (toward the left according to the orientation of  FIG. 1 ) the catch  48  resides in the gap adjacent the protrusion  56  to therefore hold and locked the lens in place. Also referring to  FIGS. 2D and 2E , the catch  48  is disposed within an undercut  46 , and the hook or protrusion  56  of the lens  22  resides within the gap  58  when the mechanism  30  is slid to the locked position. The catch  48  may be tensioned as by a spring  50 . The spring  50  resides within a cavity formed above the catch  48 . In order to urge the mechanism  30  to a normally closed or locked position against the lens, a retaining spring  38  can be used ( FIG. 2B ), which is mounted within a rear opening  40  formed in the body  32  of the mechanism  30 . One end of the spring  38  is inserted within the opening  40 , and the opposite end protrudes beyond the body  32  and is placed in contact with the abutting surface of the end piece  18  within the slot  54 . As also shown in  FIG. 2E , the mechanism  30  may include a removable panel  52  to ease assembly of the components to include installing the catch  48  and spring  50 . 
         [0068]    In order to remove the lens  22 , a user grasps the mechanism  30  and slides it towards the right, such that the catch  48  is removed from engagement with the hook  56 . The catch  48  has a chamfered edge ( FIG. 2E ), which allows it to be easily slid over the top edge of the hook  56 , assuming adequate force is applied against the mechanism  30 . The user holds the mechanism  30  in the unlocked position, and then rotates the lens  22  away from the frame, resulting in the extensions  23  being separated from their corresponding grooves in the frame  12 . The user may then replace the removed lens with another lens by simply aligning the new lens with the frame  12 , placing the one or more extensions  23  within their corresponding grooves in the frame, and releasing the mechanism  30  allowing it to slide towards the left, thereby engaging the mechanism with the newly replaced lens. 
         [0069]    Referring to  FIG. 3 , another embodiment is illustrated with respect to a different form of the securing mechanism, shown as a securing mechanism  100 . In this embodiment, the manner in which the securing mechanism locks or engages the lens is by a friction fit between the securing mechanism and the facing surface of the lens  22 . Referring to  FIGS. 4A-4C , the securing mechanism  100  is shown as including a body  102  and a protruding tongue or extension  104  that fits within a corresponding shaped groove  105  formed on the facing surface  22  of the lens. Referring more specifically to  FIG. 4B , the tongue  104  has a smaller neck  106  such that in order to insert the tongue  104  within the groove  105 , the opposing edges  109  of the groove  105  must be slightly spread in order to receive the tongue  104 . 
         [0070]    Referring to  FIG. 4C-4E , the mechanism  100  may be mounted to the end piece  18  in a reverse arrangement as compared to the first embodiment. More specifically, the securing mechanism  100  includes a gap  108 , and an opposing pair of flanges  111  extend toward one another, thereby forming a narrower area within the gap  108  directly between the flanges  111 . The flanges  111  are mounted within the slot  54  of the end piece  18 , thereby allowing the mechanism  100  to slide within the slot  54 . The lower edge of the end piece  18  is retained within the gap  108 .  FIG. 4E  also illustrates a recess  110  formed on the rear surface of the body  102  which is adapted to receive the lens  22 , thereby facilitating the mating relationship of the groove  105  of the lens  22  and the tongue  104 . 
         [0071]    In order to remove the lens for the embodiment shown in  FIG. 3 , the user grasps the mechanism  100 , and applies enough force so that the tongue  104  is removed from within the groove  105 . The lens  22  is removed, and replaced with another lens. The user then slides the mechanism  100  to the left with enough force applied to place the tongue  104  back within the groove  105 . In order to provide a mechanical assist for placing the securing mechanism in the locked position, it is also contemplated that the orientation of the hinge  20  and the temple  16  within the hinge  20  can be used for applying force to the securing  100  mechanism. More specifically, the rear edge  112  of the mechanism  100  can be positioned so that it will make contact with the forward edge  17  of the temple  16  when the temple is rotated to align the temple  16  with the end piece  18 , as if the sunglasses were being prepared to be worn. Accordingly in  FIG. 3 , the position of the hinge  20  is shown as being located closer to the mechanism  100 , which can accommodate this functionality. Therefore in this configuration, manual force by the user is required to unlock the securing mechanism by pulling the mechanism towards the right (according to the view of  FIG. 3 ). However, a mechanical assist can be provided to move the mechanism to the locked position by simply rotating the corresponding temple so that the forward edge  17  of the temple contacts the rear edge  112  of the mechanism  100 . Further, the forward edge  17  of the temple can be used to further assist in maintaining the mechanism  100  in the locked position by trapping or holding the rear edge  112  of the mechanism  100  against the forward edge  17 . 
         [0072]    Referring to  FIGS. 5 ,  5 A, and  6 A- 6 D, another embodiment of the present invention is provided. In this embodiment, the securing mechanism  120  includes a body  122  and a rear locking tab  124 . The locking tab includes a post  126  that is frictionally received between guides  128 . A “snap” fit can be achieved by providing the post with a slightly enlarged end  127  received in opposing grooves  129 . The mechanism  122  is slidable within the opening  54  of the end piece  18 , and is urged to a normally closed or locked position by a spring  130  mounted within a spring housing  132  integral with the end piece  18 .  FIG. 5A  also illustrates that the end piece  18  may be formed with a channel  134 , thereby reducing the degree to which the mechanism  120  protrudes from the exposed face of the end piece  18 . 
         [0073]    In the embodiment of  FIG. 5 , the front or forward edge  136  of the mechanism  120  engages a slot  138  formed in the facing surface of the lens  22  to hold the lens in place. This positional engagement configuration does not require the mechanism  120  to frictionally engage the lens  22 , and the lens is rather held in place by the complementary shaped forward edge  136  and slot  138 . Although the hinge  20  in  FIG. 5  is shown as being separated from the mechanism  120 , the hinge  20  can be located such that the forward edge  17  of the temple  16  can be used as mechanical assist to move the mechanism  120  towards the closed position, as described with respect to the embodiment of  FIG. 3 . Therefore, it should be understood that each of the embodiments disclosed herein can adopt the mechanical assist feature by locating the hinge  20  and forward edge  17  of the temple  16  near the securing mechanism. 
         [0074]    Referring to  FIG. 7A , yet another embodiment is illustrated. In this embodiment, the securing mechanism  140  includes a body  142 , a rear flange  144 , and a web  146  that interconnects the body  142  and the flange  144 . As shown best in  FIG. 8C , the mechanism  140  is slidable within the opening  54  of the end piece  18 , similar to the sliding capability of the mechanism in the other embodiments. In addition to the extensions  23  formed on the opposite side of the upper edge of the lens  22 , the lens also may also include a magnet  150  that is used in conjunction with a magnet  152  attached to the mechanism  140  to assist in maintaining the mechanism in the closed position. More specifically, as best seen in  FIG. 8B , the rear side of the mechanism  140  is illustrated in showing the magnet  152  mounted near the forward end of the mechanism  140 . When the mechanism is advanced to its locked position by moving it to the left (according to the orientation of  FIG. 7A ), the magnet  152  aligns with the magnet  150  on the lens. The two magnets  150  and  152  provide a force for the mechanism  140  to remain in the locked position. The mechanism  140  may include an indentation  147  sized for receiving a thumb or finger of a user to assist in sliding the mechanism  140 . This embodiment also includes a spring opening  148  formed on the end or trailing edge of the mechanism  144  for receiving a retaining spring  149 , thereby urging the mechanism  142  toward the normally locked position. 
         [0075]    Referring to  FIGS. 9A-13B , another embodiment is illustrated. More particularly, a securing mechanism  30  is shown from an exterior perspective in  FIG. 9A  and an interior perspective in  FIG. 9B . The securing mechanism  30  is positioned on the end piece  18  of the frame  12 . As illustrated, the securing mechanism  30  is utilized with separate or dual lenses  22 . It should be appreciated that the securing mechanism  30  may also be used with a mono lens. The securing mechanism  30  is illustrated in  FIG. 10 . The securing mechanism  30  comprises an exterior panel  160  and a rear locking tab  162 . For assembly purposes, these components are constructed separately and attached by a screw  164 , although other means for connecting the two components are known to those of skill in the art. Branding information or other indicia, such as the letter “N” illustrated in  FIG. 9A , may be part of the panel  160 . As seen in  FIG. 10 , a web  166  also forms part of the securing mechanism  30  and further functions to interconnect the locking tab  162  in a spaced relation relative to the exterior panel  164 . The web  166  includes a shoulder portion  168  having a first surface  170  that is generally parallel to the inside surface  172  of the locking tab  162 . The surfaces  170  and  172  form a channel  174  to receive a perimeter edge portion of a lens  22 . 
         [0076]      FIG. 12A  shows an outside or exterior view of the end piece  18  of a frame, similar to that illustrated in  FIG. 9A , but with the securing mechanism  30  removed. The frame forms a channel  180  that receives the upper perimeter edge of a lens  22 . An aperture  182  is formed through the end piece  18 . When the securing mechanism  30  is assembled, the web  166  is positioned within the aperture and moves back and forth between opposite ends of the aperture  182 . The inner surface  184  of the outer panel  164  slides along surface  186  of the end piece  18 . As illustrated in  FIG. 12B , the outer panel  160  and web  166  are partially assembled in the end piece  18  with the rear locking tab  162  and screw  164  removed. The inner surface  172  of the locking tab  162  slides on surface  186 . 
         [0077]    An operational sequence for the securing mechanism  30  is shown in  FIGS. 12A , B and C. In  FIG. 12A , the securing mechanism  30  is in a locked position securing a lens  22  relative to a frame  12 . In addition, the temple or ear stem  16  is shown in a folded or closed position. As illustrated, the hinge  20  and the planar end portion  188  are visible. When the ear stem  16  is in an open or unfolded position, the planar end portion  188  blocks movement of the securing mechanism  30 . Turning to  FIG. 12B , the securing mechanism has been moved to the left or unlocked position. As a result, the securing mechanism is detached from the lens  22 . As shown in  FIG. 12C , with the securing mechanism  30  in an unlocked position, the lens  22  may be detached from the frame  12 .  FIGS. 13A and 13B  show the securing mechanism  30  and lens  22  in an unlocked state and locked state, respectively. In the locked state ( FIG. 13B ), the peripheral edge of the lens is engaged with and secured by the channel  174  formed between the surfaces  170  of the web  166  and surface  172  of the locking tab  162 . To secure lens  22  to the frame  12 , the lens  22  is first properly oriented and positioned within channel  180  of the frame  12 . The securing mechanism may either be manually moved from an unlocked position to a locking position, or alternatively this may be accomplished by unfolding and opening the ear stem. In the latter context, the planar portion  188  abuts the end of the securing mechanism and pushes it into a locked position upon fully unfolding the ear stem  16 . 
         [0078]    In accordance with the present invention, various embodiments are provided for a securing mechanism used to releasably secure a lens within/against the frame of eyeglasses. The invention is adapted for any type of optical eyewear, but may be considered especially adapted for use in connection with removable sunglass lenses, which may be either prescription or nonprescription lenses. The mechanism enables a user to quickly and easily facilitate removal and replacement of lenses, without the need for tools. The removable lenses are not limited to any particular configuration, and therefore, the invention provides a versatile solution for replacement of lenses utilizing a single sunglass frame assembly. In addition and conversely, it is also contemplated that one or more sets of lenses may be switched between multiple frames. Thus, a user may have multiple frames for different purposes and/or occasions and may wish to utilize a single set of lenses with multiple frames or multiple sets of lenses with multiple frames. 
         [0079]    The sunglasses construction of the present invention may incorporate a pair of securing mechanisms, one for each separately removable lens. Alternatively, the invention may incorporate a single securing mechanism for a mono-lens configuration.