Abstract:
Glasses such as bifocals, which have refractive lenses which are rotatable at least between two positions. A manual control rotates the lenses such that if bifocal, the relatively small, high magnification zone of each lens can be moved to a high position opposed to the usual low position of fixed bifocals. The user is spared the necessity of holding the head at an awkward posture when viewing overhead objects.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   This application claims the benefit of the filing date under 35 USC 119(e) of the filing date of U.S. Provisional Application Ser. No. 61/092,039, filed Aug. 26, 2008, the contents of which are incorporated herein by reference. 

   FIELD OF THE INVENTION 
   The present invention relates to glasses and more particularly to glasses wherein the refractive lenses are pivotally movable to two different positions. 
   BACKGROUND OF THE INVENTION 
   Corrective glasses typically have lenses that have been ground or otherwise formed to provide refraction according to a prescription particular to the user. Typically, refractive lenses are mounted in a frame which encircles each of the two lenses and extends to the ears for support. 
   Bifocal lenses are ground or formed to accommodate two different refractive characteristics at two locations within one lens. Typically, as a person ages, his or her eyes lose elasticity and are unable to focus at close ranges as they once did. Bifocals have two areas of different refractive characteristics so that an area providing relatively great magnifications permits the user to undertake activities such as reading, while the rest of the lens is directed to more distant visual tasks. 
   From time to time, a person who needs bifocal lenses must use the high magnification area of the lenses while viewing in a body position which may be quite different from that for reading. For example, repair technicians, building mechanics, and others who perform manual tasks must from time to time work in areas that are obstructed to direct access, or access which would be easily viewed if the person had perfect vision. Because the eyes must align in a particular way, it may be necessary for people who are working in tight quarters, or who must look upwardly to perform a particular task, to have to hold their heads in unnatural and awkward orientations in order to utilize the relatively small area or zone of bifocal lenses which provide relatively great magnification. Illustratively, a person may need to tilt his or her head backwardly to a great extent so that the line of sight passes through the high magnification zone while looking in an upward direction. 
   Holding the head in this unnatural and awkward position can cause muscle strain and other objectionable consequences, so that the task can become difficult and unpleasant if not entirely impossible. 
   The prior art has a need for increasing versatility of bifocal type glasses to ameliorate the unnatural and awkward body positions which are occasionally necessary given today&#39;s glasses configurations. 
   SUMMARY OF THE INVENTION 
   The present invention addresses the above stated need by providing eyeglasses in which the refractive lenses can pivot or rotate about a generally horizontal axis. When used with bifocal lenses, it is possible to position the high magnification zone of the refractive lenses such that the eyes can, with the head held at an orientation at or near the usual position for horizontal viewing, establish a line of sight through the high magnification zone which is achievable in conventional bifocal glasses only by severely tilting the head. This enables a person to do many overhead tasks which would become impossible with conventional bifocal glasses. 
   The example of bifocal lenses is only one application of the invention. Another example is glasses having color or other filters located in zones in a pattern similar to that of bifocal glasses. In certain tasks, such as welding for example, it may be desirable to have a color filter or light mask in the field of vision in one limited zone to permit close work, with relatively ordinary viewing characteristics prevailing elsewhere in the field of vision. Reflective characteristics may also be arranged according to the novel scheme. 
   The novel glasses may have an axle which engages the affected lens to rotate the latter. The axle may have a dial, wheel, lever, or other graspable or manipulable member which permits the user to rotate the affected lenses to various positions. 
   The axle may act on the lenses directly or alternatively, may act on an inner frame which holds the lenses securely. The inner frame may fit closely to an outer frame having a socket for each lens which is framed by the inner frame. 
   It is an object of the invention to provide glasses having lenses having zones with different optical effects to be manually adjustable so that one zone can be selectively repositionable so that the selected zone can be viewed in at least two different locations relative the glasses frame. 
   It is an object of the invention to ameliorate overhead vision using glasses having different optical effects in different zones, so that unpleasant and awkward positioning of the head is eliminated or reduced. 
   It is an object of the invention to provide improved elements and arrangements thereof by apparatus for the purposes described which is inexpensive, dependable, and fully effective in accomplishing its intended purposes. 
   These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Various objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein: 
       FIG. 1  is a perspective view of eyeglasses according to at least one aspect of the invention. 
       FIG. 2  is a side view of the eyeglasses of  FIG. 1 , showing rotation of the lenses according to an aspect of the invention. 
       FIG. 3  is a side view similar to  FIG. 2  but showing further rotation of the lenses. 
       FIG. 4  is a front view of the eyeglasses of  FIG. 1 , showing the lenses fully rotated to a new operative position. 
       FIG. 5  is a detail view of the left center of  FIG. 4 , drawn to enlarged scale. 
       FIG. 6  is a detail view of eyeglasses according to another aspect of the invention, and is drawn to enlarged scale. 
       FIG. 7  is a front detail view of a component of eyeglasses according to still another aspect of the invention. 
   

   DETAILED DESCRIPTION 
     FIG. 1  shows a set of eyeglasses  10  of the type having lenses  12 ,  14  each including at least two zones  16 ,  18  and  20 ,  22 , respectively, of different optical effects. Zones of different optical effects refers to treatment of light impinging on the eye of the wearer. Illustratively, the eyeglasses  10  may be of the bifocal type wherein a first zone  16  or  20  is intended for magnifying images for example to enable reading. A second zone  18  or  22  is intended for general vision. The lenses  12 ,  14  may be ground or formed to a prescription which may for example encompass correction of astigmatism as well as correcting for either nearsightedness or farsightedness. The zones  16 ,  18 ,  20 ,  22  may all correct for astigmatism, nearsightedness, farsightedness, or a combination of these, as well as differing in magnification or focal characteristics. 
   Correction of astigmatism, nearsightedness, and farsightedness are examples of optical effects. Other optical effects include interposing with respect to the eye a masking filter for reducing impinging light, a color filter for altering perception of impinging light, a polarizing lens, a fresnel lens, or any device which alters the pattern of light from that which would strike the eye in the absence of a device to alter the impinging light. 
     FIG. 1  shows the lenses  12  and  14  in one of several positions of use. Each lens  12  or  14  may be held within an inner frame such as the inner frame members  24 ,  26  which encircle and hold the respective lenses  12 ,  14 . The eyeglasses  10  comprises a frame  28  which is a structural member which supports the lenses  12 ,  14  in appropriate or operative position on the user&#39;s head, and may include at least one head engaging member for further anchorage, such as the earpieces  30 ,  32 . The frame  28  may comprise an outer frame such as the outer frame members  34 ,  36  which cooperates closely with and surrounds the inner frame members  24 ,  26 . 
     FIGS. 2 and 3  depict progressive rotation of the lenses  12  and  14  from the position shown in  FIG. 1  to a newly selected position. It should be appreciated that the lenses have the ability to rotate in either direction. To move the lenses  12  and  14 , a pivotal controller is provided. The pivotal controller may comprise two circular members such as wheels or dials  38 ,  40  (visible in  FIG. 1 ) which project from the frame  28  so as to be accessible to finger manipulation to rotate the inner frame members  24  and  26  associated to their corresponding lenses  12 ,  14  (also visible in  FIG. 1 ).  FIG. 4  shows the lenses  12 ,  14  repositioned in a newly selected position. The pivotal controller will be understood to include a suitable rod or axle (not visible in  FIG. 1 ) which connects the respective dials  38 ,  40  to their associated lenses  12 ,  14  or inner frame members  24 ,  26 . 
   The pivotal controller is disposed to rotate the first lens  12  and the second lens  14  about an axis such as the axis  42  between at least a first position and a second position. In the first position (shown in  FIG. 1 ), the first zone  16 ,  20  of the first lens  12  and the second lens  14  is in line of sight when the person wearing the eyeglasses  10  is looking in one direction with the head held in the normal position. In the second position, the first zone of the same lens, such as the first zone  16  of the lens  12  is in line of sight when the person is looking in an upward direction relative to the one direction, with the head held in the same normal position. 
   It should be noted at this point that orientational terms such as up and down, left and right, and others refer to the drawing as viewed by an observer. The term “normal position” refers to a person standing upright with the eyes focused horizontally. In this position, the length of the earpieces, such as the earpieces  30 ,  32 , will usually be horizontal. 
   In summary, the lenses  12 ,  14  are repositionable so that a selected zone, such as the zones  16 ,  20  can be viewed selectively at two different locations. 
   The eyeglasses  10  may comprise a position lock mechanism  21 , as illustrated in  FIG. 5  and further described below, and would be disposed to releasably maintain at least one lens, such as the lens  12  selectively in the two discrete rotational positions shown in  FIGS. 1 and 4  upon being rotated into the respective discrete rotational positions. Illustratively, and referring now to  FIG. 5 , the dial  38  may comprise a recess  44  which may receive a ball  46  which is urged towards the recess  44  by a spring  48 . The location of the recess  44  is selected such that it aligns with the ball  46  when the lens  12  is in one of the two operative positions shown in  FIGS. 1 and 4 , and a corresponding recess  50  is aligned with the ball  46  when the lens  12  is in the other of the two operative positions. An axle  52  which is rotated by the dial  38  is seen in  FIG. 5 . 
     FIG. 6  shows a pivotal controller comprising a lever  54  which is provided in place of the dial  38  of  FIG. 5 . The frame  28  of the eyeglasses  10  may be modified to conceal the lever  54  if desired, provided that the lever  54  project from the frame  28  so as to be accessible to finger manipulation to rotate the pivotal controller and at least one of the first lens  12  and the second lens  14 . 
     FIG. 7  shows an aspect of the invention wherein an inner frame member  100  spans and connects both a first lens  112  and also a second lens  114 . Lenses  112  and  114  are linked by a nose bridge  106 . The nose bridge  106  can be rigid but is preferably constructed of a semi-flexible material such that when worn by the wearer it is able to conform to the wearer&#39;s nose regardless of orientation. The first lens  112  may comprise a first zone  116  and a second zone  118  which may be structural and functional counterparts to the first zone  16  and the second zone  18  of  FIG. 1 . Similarly, the second lens  114  may be the structural and functional counterpart to the second lens  14  of  FIG. 1 , also composed of a first zone  120  and a second zone  122  corresponding to the first zone  20  and the second zone  22  of  FIG. 1  respectively. It will be apparent that rotation of the inner frame member  100  will rotate both the first lens  112  and also the second lens  114 . This arrangement assures that the pivotal controller, such as the dial  138 , rotate both the first lens  112  and the second lens  114  simultaneously. The inner frame member  100  may comprise a stub  108  which may be connected to another pivotal controller (not shown) or alternatively may provide the function of a journal to support the end of the inner frame member  100  which is opposite the dial  138 . 
   It should be understood that components presented in the singular may be provided in the plural, and vice versa, where feasible. Illustratively, the inner frame members  24 ,  26  of  FIG. 1  may be modified to become unitary or integral with one another, as seen in the example of the inner frame member  100 . 
   In another example, the pivotal controller may be provided as two devices each rotating or pivoting one of the lenses, such as the lenses  12 ,  14 , independently of the other. The position lock may also be provided as two independently acting position locks. 
   The present invention is susceptible to modifications and variations which may be introduced thereto without departing from the inventive concepts. For example, although the position lock been described with respect to the spring urged ball  46 , it could take other forms and other locations. An interference finger (not shown), for example such as a ratchet and pawl arrangement, could be provided. 
   While the present invention has been described in connection with what is considered the most practical and preferred embodiment, it is to be understood that the present invention is not to be limited to the disclosed arrangements, but is intended to cover various arrangements which are included within the spirit and scope of the broadest possible interpretation of the appended claims so as to encompass all modifications and equivalent arrangements which are possible.