Sunglasses with visor

Plastic sunglasses comprise a transparent lens piece, a pair of temple pieces attached to the ends of the lens piece, and an opaque visor which snap-locks onto the top of the lens piece. The visor has a long curved front face with L-shaped ends, an angular top face for projecting inwardly across the top of the lens piece, and separate hooks projecting inwardly from the inner ends of the visor behind corresponding L-shaped shoulders. A visor connector at the top of the lens piece includes a curved upright wall with generally L-shaped ends. The wall is recessed from a curved ridge with generally L-shaped ends extending across the front of the lens piece. The opposite ends of the visor connector include L-shaped slots in its bottom front face which interlock with the L-shaped shoulders on the bottom inside face of the visor. The visor is interlocked with the visor connector by engaging the shoulder at one end of the visor with a corresponding slot on the lens piece, engaging the hook at the opposite end of the visor with a rear edge of the lens connector wall, and pressing down on the opposite end of the visor so the hook and shoulder move downwardly and apply tension to the end of the visor until the shoulder in front of the hook snap-locks into the slot at the opposite end of the visor connector.

FIELD OF THE INVENTION 
This invention relates to eyewear, and more particularly, to plastic 
sunglasses having a releasably interlocking opaque visor. 
BACKGROUND OF THE INVENTION 
Plastic sunglasses in the past have been made in various styles to 
intercept light along the top and around the sides of the glasses. 
Wraparound sunglasses are an example of glasses which can intercept the 
light at the sides of the glasses. Light rays which can enter the user's 
eyes from above can create extreme discomfort. 
The present invention provides plastic sunglasses which include a plastic 
transparent lens piece and a separate opaque visor which snap locks onto 
the top of the lens piece to block light rays which would otherwise enter 
the user's eyes from above. The visor has an additional function in that, 
being a separate piece, it can provide a style statement by using colors 
that can contrast with or match the color of the transparent lens piece. 
In providing such a snap-on visor, the means for attaching the visor to the 
top of the lens piece can be a difficult problem. There is a need to 
ensure that the visor is held firmly on the lens piece without easily 
falling off or becoming loosened, especially during physical activities 
such as running or skiing, for example. The snap lock feature also should 
be conducive to easily removing the visor and replacing it with a similar 
one of a different color without substantial difficulty. It is 
particularly desirable that such a snap locked visor be interlocked with 
the top of the lens piece and removed without requiring special tools or 
the like. 
SUMMARY OF THE INVENTION 
Briefly, one embodiment of this invention comprises sunglasses which 
include an elongated unitary lens piece made from a bendable plastic 
material which is transparent to light passing through an optical area of 
the lens piece. An elongated visor made from an opaque bendable plastic 
piece snap locks onto the top of the lens piece. A visor connector at the 
top of the lens piece includes an upright front wall extending across the 
front of the lens piece. An elongated ridge extends across the front of 
the lens piece below the front wall of the visor connector. A pair of 
slots are formed in the bottom ends of the front wall of the visor 
connector. The front wall has upright rear edges projecting upwardly above 
the slots. The visor has an upright front face, with an angular top face 
projecting inwardly from the front face of the visor. A separate hook at 
each end of the visor projects inwardly from the front face of the visor, 
and corresponding shoulders extend inwardly in front of each hook. The 
visor is interlocked with the visor connector by engaging each shoulder of 
the visor with corresponding slots on the front wall of the visor 
connector. Each hook on the visor is engaged with each upright rear edge 
of the front wall of the visor connector. The front face of the visor 
overlies the front wall of the visor connector, with the bottom edge of 
the visor resting on the ridge along the front of the lens piece. The top 
face of the visor extends over and projects inwardly from the front wall 
of the visor connector. The top face of the visor extends over the space 
between the top of the lens piece and the user's face. The opacity of the 
visor blocks a substantial amount of light rays across the top and upper 
front portion of the gasses. 
The opaque visor can be easily snap locked onto the top of the lens piece. 
As an example, the hook at one end of the visor can be hooked behind the 
rear edge of the visor connector wall, with the shoulder in front of the 
hook disposed in the slot at the end of the visor connector wall. The hook 
at the opposite end of the visor then can be engaged with the rear edge of 
the visor connector front wall and the visor pushed downwardly until the 
shoulder at the opposite end of the visor snap locks into its 
corresponding slot. This arrangement provides means for quickly and easily 
attaching or detaching visors to or from the top of the sunglasses. 
Moreover, the opacity and angular construction of the visor provides 
substantial blockage of light across the top of the lens piece to provide 
protection from the vertical light rays, producing a very pronounced 
comfort level for the user. 
In a further embodiment of the invention, the temple pieces are mounted to 
the ends of the lens piece by a mounting means providing a spring-like 
snap action when rotating the temple pieces from their folded position to 
their open position. This mounting means retains the temple pieces under 
tension in their open position to resist rotation away from the open 
position so that the user can safely and conveniently put on the 
sunglasses. 
These and other aspects of the invention will be more fully understood by 
referring to the following detailed description and the accompanying 
drawings.

DETAILED DESCRIPTION 
FIGS. 1 through 3 illustrate multi-component plastic sunglasses 10 in their 
assembled form. The sunglasses include an elongated curved lens piece 12 
having a continuous raised optical surface with left and right lens areas 
14 and 16 on opposite sides of a recessed nose piece 18. The lens piece is 
curved lengthwise to match the contour of the user's face, in the usual 
manner, so that the left and right lens areas can be positioned in the 
left and right eye field of vision when the glasses are worn. The nose 
piece has a flanged inverted U-shaped nose rest which also adds rigidity 
to the lens piece. The lens piece has generally L-shaped left and right 
wraparound ends 20 and 22 also adding rigidity to the ends of the lens 
piece. 
An elongated curved visor piece 24 is releasably fastened to a top portion 
of the lens piece with an interlocking snap fit. The visor piece has an 
upright front face 26 for extending across the top front of the glasses 
above the optical area. An elongated top face 28 of the visor piece 
extends at an angle inwardly from the front face of the visor piece, over 
the top edge of the lens piece. The visor piece also has generally 
L-shaped left and right wraparound ends 29 and 30 located above the 
wraparound ends of the lens piece. 
A pair of elongated left and right temple pieces or temple bars 32 and 34 
are releasably attached to upper and lower inside portions of the left and 
right wraparound ends of the lens piece. The temple pieces have a wide 
front end portion 36 with a raised surface. The front end of each temple 
piece has the same height as the adjacent wraparound end portions of the 
lens piece and the attached visor piece. The bottom end portions of the 
temple pieces are narrowed down to form recessed ear mounting sections 38. 
The lens piece and the temple pieces are preferably injection molded from a 
transparent bendable hard plastic material such as optical quality 
polycarbonate. The lens piece and temple pieces are preferably tinted with 
an appropriate color to reduce transmission of light to the eyes of the 
wearer. The visor piece is preferably made by injection molding it from an 
opaque bendable plastic material such as polycarbonate. The plastic lens 
piece and visor piece are both bendable sufficiently so that their ends 
can be flexed inwardly toward one another with the lens piece and visor 
recovering their original shape when the bending force is released. Both 
pieces also are resiliently bendable in torsion. 
The visor piece provides an opaque upright wall of essentially uniform 
width across the entire front portion of the lens piece immediately above 
the lens areas, with the opaque visor also extending over the top of the 
glasses and projecting inwardly away from the inside face of the glasses. 
The opaque visor blocks the intense sun rays from the top that would 
normally pass through the space between the upper inside edge of the 
glasses and the user's face and also through the top of the glasses 
immediately above the eyes. The opaque visor thereby blocks a substantial 
amount of light to provide greatly improved comfort for the eyes when 
exposed to the intense rays of the sun. In addition, the opaque visor 
piece can be attached or unfastened from the top of the glasses and 
thereby provide a means for interchanging the visor piece in various 
colors to match or contrast the color of the glasses, if desired. 
The visor piece is releasably attachable to the top of the lens piece in an 
extremely tight snap-on fit which avoids the visor piece from loosening or 
falling off of the lens piece. The visor piece remains in a fixed position 
without loosening even when the lens piece is subjected to extreme amounts 
of bending or twisting. However, the visor piece can be easily removed 
from the lens piece, if desired, by prying the two pieces apart with 
oppositely directed forces applied without the need for any special tools 
or the like. 
Detailed construction of the various components of the sunglasses will now 
be described. 
FIGS. 4 through 8 illustrate construction of the lens piece 12. The raised 
optical area extends over most of the front surface of the lens piece. The 
border of the optical area is shown best at 40 in FIG. 4. An elongated 
visor connector member 42 extends across a top portion of the lens piece. 
The visor connector member is recessed with respect to the front plane of 
the lens area, behind an elongated ridge 44 extending across the front of 
the lens piece below the visor connector member. The visor connector 
member is preferably of substantially uniform length from end-to-end, 
having a top edge 46 spaced above and extending substantially parallel to 
the ridge 44, preferably about one-half inch above the ridge. The visor 
connector member also includes an elongated curved front face matching the 
curvature of the lens area, together with upwardly and inwardly angled 
wraparound end walls 50 and 52 at left and right ends of the member. The 
end walls 50 and 52 are L-shaped (see FIG. 6) and match the L-shaped 
contour of the left and right wraparound ends 20 and 22 of the lens piece. 
The ridge 44 extends continuously across the front of the visor connector 
member, and the ridge has corresponding left and right L-shaped end 
surfaces 54 and 56 at the bottom front of the L-shaped ends of the visor 
connector member. Left and right rear edges 55 and 57 of the visor 
connector member extend above the L-shaped end surfaces of the ridge. As 
shown best in FIG. 7, the visor connector member is preferably spaced to 
the rear of and extends upwardly and inwardly at an angle with respect to 
the lens area of the lens piece. 
A pair of left and right connector slots 58 and 60 are formed at the bottom 
end portions of the visor connector member. These slots are of narrow 
profile and are located on the front face of the visor connector member 
immediately above the top surface of the ridge 44. More specifically, the 
slots are each generally L-shaped to match the contour of the L-shaped 
ends of the visor connector member, and the base of each slot is in the 
same plane as the upper surface of the L-shaped end portion of the 
adjacent ridge. The inner end of each slot (on the front side of the visor 
connector member) terminates a short distance from the corner of the visor 
connector member. The opposite ends of the slots open outwardly toward the 
rear of the lens piece, below the rear edges 55 and 57 of the visor 
connector member. The L-shaped slots 58 and 60 are thus formed underneath 
the L-shaped ends of the visor connector member immediately above the 
L-shaped end portions of the ridge which extends across the upper portion 
of the lens piece. The indentation formed by each slot leaves an inwardly 
projecting shoulder 61 on the inside ends of the visor connector member. 
Mounting tabs for the temple pieces 32 and 34 are formed on the upper and 
lower inside corners of the lens piece. The mounting tabs include left and 
right upper mounting tabs 62 and 64 integrally formed with the lens piece 
immediately below the connector slots 58 and 60. The upper surfaces of the 
upper mounting tabs are essentially in the same plane as the ridge 44 and 
its L-shaped end surfaces 54 and 56. The mounting tabs for the temple 
pieces also include left and right lower mounting tabs 66 and 68 
integrally formed on the lower inside corners of the lens piece. A pair of 
upper and lower holes 70 and 72 in the right upper and lower tabs are 
aligned on a common axis extending at an angle of about 15.degree. 
relative to vertical. Similarly, a pair of upper and lower holes 74 and 76 
in the left upper and lower tabs are also aligned on a common axis 
extending at the same angle. 
The front face of the visor connector member 42 has an elongated recessed 
slot 78 extending parallel to and spaced above the ridge 44. The slot 78 
is formed so it faces outwardly at the front center of the connector 
member. The area around the slot on the inside of the member is widened at 
80 to add rigidity around the perimeter of the slot. 
FIGS. 9 through 13 illustrate detailed construction of the visor piece 24. 
The curved front face 26 of the visor piece matches the curvature and 
angular orientation of the front wall 48 of the visor connector member 42. 
The height of the front face of the visor piece matches the height of the 
visor connector member from end-to-end. The L-shaped ends 29 and 30 of the 
visor piece match the L-shaped contour of the wraparound ends of the visor 
connector member. The top face 28 of the visor piece extends inwardly at 
an angle from the front face of the visor piece. The top face 28 of the 
visor piece has generally L-shaped left and right wraparound end portions 
82 and 84 above corresponding left and right wraparound side wall portions 
29 and 30 of the visor piece. Hooks 86 and 88 are formed at the base of 
each wraparound wall, and the hooks extend into the interior of the visor. 
The base of each hook is continuous with the bottom edge of the visor 
piece, as shown best in FIG. 11. Separate L-shaped shoulders 90 and 92 
extend in front of the left and right hooks 86 and 88. These shoulders are 
located at the bottom inside corners of the visor piece. The bottom 
surfaces of the shoulders are continuous with the bottom edge of the visor 
piece, and each shoulder projects into the interior of the visor piece by 
a uniform distance from end-to-end. The width of each shoulder is less 
than the length of its corresponding hook so that the hook projects 
farther into the interior of the visor piece than its adjacent shoulder. 
An elongated tab 94 projects inwardly from the front inside face of the 
visor piece. The tab is parallel to and spaced above the bottom edge of 
the visor piece. The tab is arranged so that it snap locks into engagement 
with the slotted recess 78 on the front wall of the visor connector member 
42. 
FIGS. 14 through 16 illustrate detailed construction of the temple pieces 
32 and 34. The figures illustrate the right temple piece 34. The left 
temple piece 32 is of identical but reverse configuration. As to the 
detailed construction of the right temple piece 34, flanged upper and 
lower walls 96 and 98 are integrally formed with the widened front end of 
the temple piece. These upper and lower walls taper wider toward the front 
of the temple piece and provide rigidity for the temple piece. The widened 
front end of the upper wall 96 has about the same width as the L-shaped 
ends of the visor piece, and the lower wall 98 has about the same width as 
the lower tabs on the visor piece for holding the temple pieces. The 
widened front end of the temple piece also has a short front wall 
integrally formed with the upper wall 96 and with the front end of the 
side wall of the temple piece. An upper mounting post 102 is formed 
integrally with and extends to the front of the front wall 100. The post 
102 extends upwardly from the remote end of a leg 104 which holds the post 
on the bottom of the front wall 100. The widened front end of the temple 
piece also has a short bottom wall which is integrally formed with the 
lower wall 98 and the side wall of the temple piece. A lower mounting post 
108 projects in front of the lower wall 106. The lower mounting post 108 
projects downwardly from the end of a leg 110 which holds the post spaced 
in front of the lower wall 106. The upper and lower mounting posts are 
aligned on a common axis, and the posts are adapted to fit into the 
mounting holes on the tabs of the lens piece for releasably attaching the 
temple pieces to the ends of the lens piece. The temple pieces have a 
slight amount of flexibility in the upright direction so that the mounting 
posts can be forced toward one another by a short distance under pressure 
applied to the front ends of the temple piece. This provides a means for 
fitting the posts into the space between their corresponding mounting 
tabs, whereupon a release of the bending force causes the mounting posts 
to register with the holes in the mounting tabs to securely fasten the 
temple pieces to the ends of the lens piece. 
In using the sunglasses, the visor piece 24 is releasably attached to the 
visor connector member 42 by first fitting the hook 86 at one end of the 
visor piece behind the rear edge 55 of the visor connector member, so that 
the shoulder 90 in front cf the hook 86 fits into the L-shaped slot 58 at 
the base of the visor connector member wall. The bottom edge of the 
L-shaped corner of the visor piece rests on the L-shaped upper surface 54 
at the end of the ridge 44 which extends across the front of the lens 
piece. One end of the visor piece is thereby confined within the end of 
the connector member so that the end of the visor is prevented from moving 
up or down relative to the end of the visor connector member. At the 
opposite end of the visor piece, the hook 88 is placed behind the rear 
edge 57 of the visor connector wall near the top of the rear edge. This 
positions the shoulder 92 in front of the hook on the outside face of the 
visor connector wall. This end of the visor is then pushed downwardly 
toward the slot 60 at the corner of the visor connector wall so that the 
hook 88 rides down along the ramp-like rear edge of the visor connector 
wall, while the shoulder in front of the hook rides down along the 
ramp-like outside face of the wall. This increases the tension between the 
visor piece and the visor connector member as the visor piece is pushed 
down toward the connector slot 60 at the base of the wall. Continued 
downward force finally causes the shoulder 92 in front of the hook 88 to 
snap into engagement with the connector slot 60. The hook behind the 
shoulder is held under slight tension adjacent the bottom rear edge 57 of 
the visor connector member wall. The flexibility of the plastic material 
achieves this snap lock function. 
In the locked position of the visor, the bottom of the hook 88 rests on the 
L-shaped upper face 56 of the ridge 44, and the shoulder in front of the 
hook is held tightly in place in the connector slot. The inside face of 
the visor wall 26 is held firmly against the outside face of the visor 
connector wall. The bottom edge of the visor piece is held firmly against 
the upper surface of the ridge 44. In addition, the tab 94 at the front 
center of the visor piece is engaged with the slot 78 at the front face of 
the visor connector member. Normally, a slight amount of downward force 
applied to the top center of the visor piece snap locks the shoulder into 
engagement with the slot. Engagement of the front shoulder and slot 
provides a means for preventing movement of the visor upwardly relative to 
the visor connector wall. 
The connecting means at opposite ends of the visor piece provide an 
effective means of holding the visor piece in a fixed position without any 
movement relative to the visor connector member. The visor can be easily 
removed from the visor connector member owing to the flexibility of the 
plastic materials. The end of the visor piece can be simply pried 
outwardly away from the shoulder and end of the visor connector member 
wall to release the hook from its engagement with the wall and thereby 
provide a means for sliding the end of the visor away from the end 
connector. 
FIGS. 17 and 18 illustrate an alternate embodiment of the visor piece. In 
this embodiment, the sunglasses include the same lens piece 12' with 
identical temple pieces 32'. The visor piece is modified to comprise a 
visor 112 having an outwardly projecting lens shade 114 extending 
horizontally across the top of the visor 112. Otherwise, the ends of the 
visor piece 112 snap lock into engagement with the visor connector member 
on the lens piece 12' in the same manner as described above. 
FIGS. 19 through 32 illustrate components of a system for providing a 
spring-like snap action to the temple bars as they rotate outwardly to the 
open position. When a user unfolds the temple bars 32 and 34 to the open 
position, as shown in FIG. 1, it is desirable for the temple bars to be 
held in the open position with resistance against rotation back toward 
their folded position. If the temple bars are easily movable away from the 
open position, then the ends of either temple bar can poke the user in the 
eye when the user is putting on the sunglasses. 
This problem is overcome by the snap action system of mounting the temple 
bars to the sides of the lens piece. Briefly, the snap action is produced 
by modifying the mounting tabs on opposite sides of the lens piece to 
provide ramp surfaces which cooperate with modified ramp surfaces on the 
upper and lower legs of the mounting posts at the front ends of the temple 
bars. By rotating the ramp surfaces on the temple posts into contact with 
the ramp surfaces on the mounting tabs of the lens piece, as the temple 
bars are being rotated from the folded position toward their open 
position, the temple bars will snap outwardly to the open position with a 
spring-like action and remain in the open position with a spring-like 
resistance against movement back toward the folded position. 
The preferred snap-action system for mounting the temple bars to the lens 
piece is best understood by first referring to FIGS. 19 through 21, which 
show a right end portion 200 of the lens piece with modified upper and 
lower mounting tabs 202 and 204. A similar system of modified mounting 
tabs is used on the left side of the lens piece, but is not shown for 
simplicity. The upper mounting tab 202 projects inwardly from the right 
corner of the lens piece and has a widened outer portion 206 remote from 
the front wall of the lens piece. This widened outer portion of the 
mounting tab extends inwardly from the outer edge of the tab toward a 
straight ridge 208 on the underside of the tab, which extends across a 
portion of the mounting hole 210 through the mounting tab. A long, narrow 
upper ramp surface 212 extends upwardly at an angle along the undersurface 
of the mounting tab toward the end of the lens piece. The ramp surface 212 
extends across the bottom of the mounting tab, generally along a path 
extending on opposite sides of the mounting hole 210. The ramp surface 212 
tapers toward a long, straight edge 214 at the base of the ramp, which 
then transitions into the flat bottom surface of the main portion of the 
mounting tab, adjacent the front wall of the lens piece. 
The lower mounting tab 204 has a similar ramp surface facing upwardly 
toward the upper ramp surface 212. The lower mounting tab 204 projects 
inwardly from the lower right corner of the lens piece and has a widened 
outer portion 216, an upper ridge 218 extending across an outer portion of 
the mounting hole 220, a ramp surface 222 extending downwardly, generally 
across both sides of the mounting tab on opposite sides of the mounting 
hole, terminating in a lower ridge 224 at the bottom of the ramp surface 
222. 
The ramp surfaces on the mounting legs of the temple bars are best 
understood by referring to FIGS. 22 through 27. FIG. 22 illustrates the 
outer side of the right temple bar 226 with its upper and lower temple bar 
mounting legs 228 and 230 at its front edge. Upper and lower hinge posts 
232 and 234 project upwardly and downwardly, respectively, above and below 
the ends of the upper and lower mounting legs. In this view, upper and 
lower ramp surfaces are on the opposite sides of the upper and lower 
mounting legs, and these ramp surfaces are shown at 236 and 238, 
respectively. 
The inside face of the right temple bar 226 is shown in FIG. 23, which also 
illustrates front views of the ramp surfaces 236 and 238 on the upper and 
lower mounting legs 228 and 230 of the upper and lower hinge posts, 
respectively. 
The side view of FIG. 24 shows that the upper mounting leg 228 has a 
widened section with a flat top surface 240 near the outer side of the 
temple bar. The ramp surface 236 extends downwardly at an angle away from 
the flat top surface of the leg toward the inside of the temple bar. 
Similarly, the lower mounting leg 230 has a widened section with a flat 
bottom surface 242, and the lower ramp surface 238 extends upwardly at an 
angle away from the flat bottom surface of the leg toward the inside of 
the temple bar. 
FIG. 26 is a top view of the ramp surface 236 and FIG. 27 is a bottom view 
illustrating the lower ramp surface 242. 
FIGS. 28 through 32 illustrate assembly and use of the snap action temple 
bars. FIG. 28 is a side view illustrating the folded position of the right 
temple bar with the upper hinge post 232 of the upper mounting leg 228 
inserted into the mounting hole 210 in the upper mounting tab 202 on the 
right side of the lens piece. FIG. 29 is a top view of the assembly shown 
in FIG. 28. The bottom connections of the temple bars and the connections 
between the left temple bar and the left side of the lens piece are not 
shown for simplicity, inasmuch as their functions are similar to those 
illustrated in FIGS. 28 through 32. Each temple bar is assembled to an end 
of the lens piece by inserting the hinge posts 232 and 234 into the 
mounting holes 210 and 220 at the corner of the lens piece. During 
assembly, the sides of the temple bars must be flexed to shorten the 
distance between the opposite ends of the hinge posts so that they can fit 
between the upper and lower mounting tabs for alignment with the mounting 
holes. The temple bars are made from a semi-rigid plastic material which 
allows each temple bar to be flexed by hand pressure to shorten its 
vertical dimension sufficiently to insert the hinge posts into the space 
between the mounting holes. Once the hinge posts are aligned with the 
mounting holes, the applied pressure is released and the hinge posts snap 
into engagement with the mounting holes. Inasmuch as the unstressed 
vertical distance between the hinge posts is normally greater than the 
corresponding vertical distance between the mounting tabs, when the hinge 
posts are snapped into engagement with the mounting holes, there remains a 
constant upward and downward spring force naturally applied to the upper 
and lower mounting tabs by the hinge posts. This pressure retains the 
hinge posts in the mounting holes without any lost motion. 
FIG. 28 shows the right temple bar 226 in its folded position in which the 
upper hinge post 232 is inserted into the mounting hole 210 of the upper 
mounting tab 206. In this folded configuration of the temple bar, shown in 
FIGS. 28 and 29, the flat top surface 240 of the post mounting leg 228 
engages the bottom of the upper mounting tab 206. These engaging portions 
of the post mounting leg 228 and the upper mounting tab 206 are at their 
widened portions, which causes the leg 228 to be naturally pushed upwardly 
with a spring force by the natural flexibility of the semirigid, plastic 
temple bar. The flat bottom surface 242 of the lower post mounting leg 238 
also is pressed into pressure contact with the widened bottom portion 216 
of the lower mounting tab so that, in the folded position, the hinge post 
mounting legs apply upward and downward spring pressure to their means of 
connection to the ends of the lens piece. FIG. 29 shows that in the folded 
position of the temple bar 226, the ramp surfaces 212 and 236 on the 
mounting tab and on the hinge post mounting leg, respectively, are at 
right angles to one another and, therefore, are not in contact. The ramp 
surfaces are cross-hatched for clarity. 
FIG. 30 shows an intermediate position of the temple bar 226 rotating from 
a folded position of FIG. 29 toward its open position. In the partially 
open position shown in FIG. 30, the ramp surface 236 on the hinge post 
mounting leg 228 is rotating toward the ramp 212 on the underside of the 
lens piece mounting tab 202. In this position, the widened portions of the 
upper and lower hinge post mounting legs are still in spring-like pressure 
contact with the adjacent widened portions of the upper and lower temple 
bar mounting tabs. The ramp surfaces on the mounting tab and on the temple 
bar mounting leg are cross-hatched for clarity. 
Once the temple bar reaches the partially opened position shown in FIG. 30, 
further outward rotation of the temple bar, in the direction of the arrow 
in FIG. 30, ultimately causes the temple bars to snap outwardly with a 
spring action, to the open position of the temple bars shown in FIGS. 31 
and 32. As manual pressure is applied to the temple bar to rotate it 
outwardly toward its open position, the ramp surface 236 on the hinge post 
mounting leg 228 eventually comes into contact with the ramp surface 212 
on the underside of the upper mounting tab; and once the two ramp surfaces 
engage one another, the upward spring pressure of the semi-flexible 
plastic material in the temple bar post and mounting leg causes the two 
ramp surfaces to be quickly forced into contact with one another. This 
causes the ramp on the hinge post mounting leg to rapidly slide down the 
ramp on the mounting tab and automatically force the temple bar to rotate 
rapidly, outwardly with a snap action. FIG. 3 shows the cross-hatched 
engaged portions of the ramp surfaces. The temple bar is held in its open 
position by engagement of the end surfaces 250 and 252 of the lens piece 
and the mounting tab. These surfaces engage one another to act as a stop. 
While the temple bar is in the open or stop position, there is still a 
modest amount of spring pressure applied naturally (from the resilience of 
the plastic) between the upper and lower mounting legs on the temple bar 
and their cooperating connections to the upper and lower mounting tabs on 
the lens piece. This presents lost motion and resists backward rotation of 
the temple bars. 
Thus, the user can easily rotate the temple bars from the folded position 
to the open position by a slight amount of outward pressure and by 
rotating each temple bar about half way to its open position. The ramp 
surfaces then engage one another and automatically snap the temple bars to 
the open position. The temple bars are both held in a fixed position in 
the open position by the retained spring force between the temple bar 
hinge post mounting legs applying pressure to their cooperating mounting 
tabs on the lens piece. 
The snap-action temple bar system has been described in relation to a 
preferred arrangement in which the cooperating cam surfaces are on both 
the upper and lower temple bar posts and lens piece mounting tabs. 
Alternatively, the snap-action system can be provided with the cooperating 
cam surfaces being on either the upper or lower temple bar posts and lens 
piece mounting tabs. 
FIG. 33 shows an alternate configuration of the visor piece 254 in which 
the upper lip 255 of the visor piece can be modified with respect to the 
configuration shown in FIG. 12, so that its inwardly projecting opaque 
ends of the visor piece are shown to extend inwardly further from the top 
of the lens piece to provide a greater amount of light blockage in the 
regions shown at 256 and 257 near the connection of the lens piece to the 
temple bars 258 and 260. This provides a highly effective means of 
intercepting the light at the upper corners of the sunglasses where light 
would otherwise enter the user's eyes from above.