U.S. patent number 3,905,680 [Application Number 05/429,098] was granted by the patent office on 1975-09-16 for 360.degree. reflex reflector.
This patent grant is currently assigned to Beatrice Foods Co.. Invention is credited to Robert I. Nagel.
United States Patent |
3,905,680 |
Nagel |
September 16, 1975 |
360.degree. Reflex reflector
Abstract
A reflex reflector which when vertically oriented spatially is
adapted to continuously retro-reflect incident light rays
horizontally striking such anywhere within an included angle of
about 360.degree.. Such reflector uses four reflective surfaces,
arranged into two pairs of two surfaces each, the surfaces of each
pair being in opposed, parallel relationship to each other, the
pairs being oriented at 90.degree. relative to each other. Each
surface has reflex reflector facets adapted to retro-reflect over
an angle of .+-. 45.degree..
Inventors: |
Nagel; Robert I. (Skokie,
IL) |
Assignee: |
Beatrice Foods Co. (Elgin,
IL)
|
Family
ID: |
23701792 |
Appl.
No.: |
05/429,098 |
Filed: |
December 28, 1973 |
Current U.S.
Class: |
359/531; 116/28R;
116/63R; 359/532; 359/533; 404/9 |
Current CPC
Class: |
G02B
5/12 (20130101); G02B 5/124 (20130101) |
Current International
Class: |
G02B
5/12 (20060101); G02B 5/124 (20060101); G02B
005/12 () |
Field of
Search: |
;350/97-109 ;404/9-16
;116/63 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Smith; Alfred E.
Assistant Examiner: Tokar; Michael J.
Claims
I claim:
1. A reflex reflector body adapted to retro-reflect incident light
over an included angle of at least about 360.degree. measured in
one plane comprising
A. a body having four retro-reflective, generally planar surface
portions arranged into two pairs of two portions each, said
portions of each such pair of portions being generally in opposed,
parallel relationship to each other, one such pair of portions
being normally disposed relative to the other thereof, each said
portion having at least one region comprised of transparent, solid
material and having a region axis normal thereto,
B. support means holding each such pair of portions in fixed,
substantially non-overlapping adjacent relationship relative to the
other thereof,
C. each one of said regions having formed therein at least two
groups of cube corner reflector elements, all such elements each
having a central optical axis, the respective such optical axes of
such elements in each such group being disposed substantially
parallel to the respective such optical axes of the other such
elements in each such group, each one of said regions further being
retro-reflective of light directed thereon over an angle extending
up to at least about 45.degree. on a pair of opposed sides of said
region axis thereof in a first plane extending through said region
axis thereof,
D. the respective optical axes of such elements in one such group
being generally parallel to said region axis in each said
region,
E. the respective optical axes of such elements in a second such
group being inclined at a predetermined angle in one direction
relative to said region axis in each said region, and the
respective optical axes of such elements in a third such group
being inclined at a predetermined angle in a different direction
relative to said region axis in each said region,
F. the interrelationship between said groups, and said portions,
being such that, when said portions are each vertically oriented
spatially, incident light rays striking said body anywhere within
an included angle of about 360.degree. in a horizontal plane
extending horizontally through said body are adapted to be
retro-reflected.
2. The reflex reflector of claim 1 wherein said groups in each of
said portions are also adapted to retro-reflect incident light
striking either of such facets at an angle ranging from 0.degree.
up to about .+-. 20.degree. measured normally to said horizontal
plane, and each of said first planes generally coplanar with said
horizontal plane.
3. The reflex reflector of claim 1 wherein each of said portions is
similar to the other portions and the portions of each pair are
interconnected together.
4. A reflex reflector body of claim 1 wherein said respective pairs
adjoin at intersecting edge portions.
5. A reflex reflector body of claim 1 wherein said respective pairs
are in spaced relationship to each other.
6. The reflex reflector body of claim 5 wherein said spacing is
vertical.
7. The reflex reflector body of claim 5 wherein said spacing is
vertical and horizontal.
8. A reflex reflector body of claim 1 further including mounting
means.
9. A reflex reflector body of claim 5 further including mounting
means.
10. A reflex reflector body of claim 1 wherein each of said pairs
is triangularly shaped.
11. A reflex reflector body of claim 10 wherein each of said pairs
has four sides.
Description
BACKGROUND OF THE INVENTION
In many applications for reflex reflectors, there is a need for
horizontal 360.degree. viewability such as, for example, on
bicycles, on construction sites, on airport runways, on entrances
to side lanes, and the like. Because of their inherent
retro-reflective properties, it is necessary to employ a plurality
of prior art standard reflex reflectors of the molded plastic type
with flat faces in order to achieve full 360.degree. viewability
since individual such reflectors with flat faces are
characteristically viewable over angles of only about .+-.
30.degree. horizontally measured on either side of the face
thereof. There is thus a strong and long felt need in the art for a
simple, economical, reflex reflector construction employing molded
plastic (e.g. acrylic resin, polycarbonate, or the like) which can
provide 360.degree. viewability horizontally.
BRIEF SUMMARY OF THE INVENTION
The present invention is directed to reflex reflector bodies
adapted to retro-reflect incident light anywhere within an included
angle of about 360.degree., measured in one plane. Such a body
characteristically has four retro-reflective, generally planar
surface portions. These portions are arranged into two pairs of two
portions each. Each portion of each pair is generally in opposed,
parallel relationship to the other thereof. One such pair is
normally disposed relative to the other thereof. Support means hold
each pair in fixed, substantially non-overlapping adjacent
relationship to the other thereof. The interrelationship between
said portions is such that, when they are each vertically oriented
spatially, incident light rays which strike said body anywhere
within an included angle of about 360.degree. in a horizontal plane
extending through said body are adapted to be retro-reflected.
It is an object of this invention to provide a reflex reflector
body horizontally viewable anywhere within an angle of 360.degree.
using only four flattened reflective faces.
It is another object to provide such a reflector body which uses
both wide angle and standard reflex reflective molded facets in
each such face.
A further object is to provide a 360.degree. reflex reflector using
only one or two reflective bodies and having only a few
retro-reflective surfaces therein.
A still further object is to provide an optimized construction for
a 360.degree. reflex reflector, horizontally measured.
Other and further aims, objects, purposes, advantages, utilities,
and features will be apparent to those skilled in the art from a
reading of the present specification and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is an isometric view of one embodiment of a reflex reflector
of the present invention;
FIG. 2 is a transverse sectional view taken along the line II--II
of FIG. 1;
FIG. 3 is a plan view of the embodiment of FIG. 1 illustrating how
360.degree. reflex reflection is achieved therewith;
FIG. 4 is an isometric view of another embodiment of a reflex
reflector of this invention;
FIG. 5 is a plan view of the embodiment of FIG. 4;
FIG. 6 is an isometric view of another embodiment of a reflex
reflector of this invention;
FIG. 7 is an isometric view of another embodiment of a reflex
reflector of the present invention;
FIG. 8 is an isometric view of another embodiment of a reflex
reflector of the present invention;
FIG. 9 is an isometric view of another embodiment of a reflex
reflector of the present invention;
FIG. 10 is an isometric view of another embodiment of a reflex
reflector of the present invention;
FIG. 11 is an enlarged isometric view of one embodiment of a
pin;
FIG. 12 is a top plan view of the hexagonal pattern produced by a
plurality of pins in a retro-reflective reflector;
FIG. 13 is a side elevational view of one cube corner in a
retro-reflective reflector body;
FIG. 14 is a plot of the characteristic retro-reflected light
intensity produced by a plurality of facets of the type shown in
FIG. 13;
FIG. 15 is a series of plots illustrating the manner in which the
field of reflected light changes as the pin centers are angled from
a vertical position to a position inclined to the vertical;
FIG. 16 shows illustrative plots for a reflector of the type having
both standard reflector facets and wide angle reflector facets;
and
FIG. 17 is a plot illustrating the relationship between angle of
reflected light and intensity of reflected light at such angle both
horizontally and vertically for a combination of wide angle and
standard reflectors in a single reflector body.
DETAILED DESCRIPTION
Turning to the drawings there is seen in FIGS. 1 and 2 one
embodiment of a reflex reflector body of the present invention
herein designated in its entirety by the numeral 15. Body 15 is
adapted to retro-reflect incident light over an included angle of
at least 360.degree. measured in one horizontally extending plane
16. The body 15 has four retro-reflective generally planar surface
portions designated, respectively, as 18, 19, 20 and 21. Two of
these portions, portions 18 and 21, are generally in opposed,
parallel relationship one with the other, and the remaining
portions, portions 19 and 20, are likewise in generally opposed,
parallel relationship to each other. Portions 18 and 21 extend
normally in relation to portions 19 and 20. Preferably, and as
shown, portions 18, 19, 20 and 21 have substantially identical
surface reflective characteristics and each preferably has a
similar perimetric shape.
Each of the portions 18, 19, 20 and 21 has incorporated thereinto
at least three different groups of retro-reflective, prismatic
facets. The facets in each group are identical to one another. In
one group, the facets are adapted to retro-reflect incident light
striking such group at an angle ranging from about 0.degree. up to
about .+-. 30.degree. measured normally thereto in one direction
within one plane (such as a plane 16, 26 or 27 in FIG. 1, for
example). The other two such groups are adapted to retro-reflect
incident light striking such at an angle ranging from an angle
which is not greater than the maximum retro-reflectance angle of
such one group up to an angle which is at least about .+-.
45.degree. measured from a normal thereto in such plane, one of
such other groups being retro-reflective on one side of such
normal, the other of such groups being retro-reflective on the
other side of such normal.
Thus, in the embodiment 15, using portion 21 as representative each
of two different types of facets are arranged into at least two
groups integrally formed in each of the surface portions 18, 19, 20
and 21. In each of the portions 18, 19, 20 and 21, any convenient
arrangement or pattern of such groups may be employed. Thus,
portion 21 is divided into three such groups of facets, one group
being designated 23, a second group being designated 24, and a
third group being designated 25. The group 23 facets are adapted to
retro-reflect incident light striking same at angles ranging from
about 0.degree. up to about .+-. 30.degree. (measured in plane 27).
The group 24 facets are adapted to retro-reflect light striking
same at angles ranging from an angle not greater than about
30.degree. up to an angle which is about 45.degree. to the left of
perpendicular or normal line 28 in plane 27 with respect to
incident light rays striking surface portion 23 in plane 27. The
group 25 facets are adapted to retro-reflect light striking same at
angles ranging from an angle not greater than about 30.degree. up
to an angle which is about 45.degree. to the right of perpendicular
28 in plane 27. Such portions 19, 20 and 21 are similarly divided
into groups.
In the embodiment 15, each of the surface portions 18, 19, 20 and
21 has a generally square configuration, but any convenient
perimetric configuration may be employed for purposes of this
invention.
The interrelationship between such groups and such portions 18, 19,
20 and 21 is such that, when such portions 18, 19, 20 and 21 are
each vertically oriented spatially, incident light rays
horizontally striking such within an included angle of about
360.degree. extending horizontally are retro-reflected. In order to
enhance retro-reflectance viewability characteristics of a body 15,
it is preferred to have the respective portions 16, 17, 18 and 19
be further adapted to retro-reflect incident light striking same at
angles ranging from about 0.degree. up to about .+-. 20.degree.
(and more preferably .+-. 30.degree., and still more preferably
.+-. 45.degree.) measured normally thereto above and below such one
plane therethrough, such as plane 27 through representative portion
21. Thus, when the body 15 is oriented so as to have its portions
18, 19, 20 and 21 vertically spatially oriented, this direction is
vertical with respect to the other direction which is horizontal.
Such characteristics are achieved by selection of facet groups and
by arrangement thereof, as those skilled in the art will
appreciate.
The body 15 is formed of two subassemblies 30 and 31, of which
subassembly 31 is representative (see FIG. 2). Each subassembly is
formed of two pieces of molded transparent plastic, such as an
acrylic resin, a polycarbonate resin, or the like, one piece being
designated 32, the other 33. Each piece 32 and 33 has an outer
flattened face 35 and 36, respectively and an inner face 37 and 38,
respectively. Each inner face 37 and 38 has molded thereinto the
retro-reflective facets hereinabove discussed (not drawn to scale
in faces 37 and 38 in FIG. 2). Around the perimeter of each inner
face 37 and 38 is formed an inwardly turning shoulder 39 and 40,
respectively, which continuously extends about side and end edges
of each piece 32 and 33. The outside edge of each shoulder 39 and
40 is adapted to make mating opposed engagement with the other
thereof to form subassembly 31, the shoulders 39 and 40 being
conveniently sealingly bonded to each other by means of an adhesive
(not shown), or the like. Each subassembly 30 and 31 is equipped
with an ear 41 molded one half into each piece forming same (such
as pieces 32 and 33 of subassembly 31). Ears 41 aid in mounting a
body 15. Any convenient or conventional means for mounting may be
employed for mounting a body 15, as those skilled in the art will
appreciate. Subassembly 30 is conveniently mounted to subassembly
31 by a pin 42 which extends one half into each of a channel formed
in respective subassemblies 30 and 31 as shown in FIG. 1. Any
convenient means may be used to secure such subassemblies 30 and 31
together.
Body 15 (see FIG. 3) is adapted to have 360.degree.
retro-reflective characteristics because each surface portion 18,
19, 20 and 21 thereof is adapted to retro-reflect incident light
rays striking same over .+-. 45.degree. as indicated above in
reference to portion 21 and groups 23, 24 and 25 thereof. Thus,
portion 18 retro-reflects through a 90.degree. angle 44, portion 19
retro-reflects through a 90.degree. angle 45, portion 20
retro-reflects through a 90.degree. angle 46, and portion 21
retro-reflects through a 90.degree. angle 47, so 360.degree.
retro-reflection of body 15 is achieved. Preferably, each portion
18, 19, 20 and 21 is adapted to retro-reflect through an angle
greater than 90.degree. so that an overlap between adjacent
retro-reflected light areas from each portion 18, 19, 20 and 21 can
occur to some extent so as to avoid any possibility of low
retro-reflected light levels in overlap regions which might make
the body 15 harder to discern by a viewer located at a corner area
from body 15. Those skilled in the art will appreciate that
operability of the present invention does not depend upon
reflectivity from any one reflective surface in any given
hypothetical plane, such as 26, 21 or 16, or on either side of any
given normal in such plane. Body 15 is suitable for use on
construction sites, airport runways, vehicles, and the like.
In FIGS. 4 and 5 is illustrated an alternative embodiment of a
reflector of this invention which is designated in its entirety by
the numeral 48. Here a pair of triangles 49 and 50 are integrally
interconnected together at their adjoining or common apexes 51.
Each outside, vertically spaced edge 52 and 53 of respective
triangles 49 and 50 is equipped with an ear 54 and 55 for mounting
purposes. Conveniently, each triangle 49 and 50 may be formed
similarly to subassembly 31 of body 15 and then the two triangles
49 and 50 joined together at apexes 51 by an adhesive or the like
(not shown). A pin (not shown) such as in body 15 may be employed
to secure the triangles 49 and 50 together analogous to body 15.
Faces 56, 57, 58 and 59 are each similar to each other. Each
flattened outside face 56 and 57 of triangle 49, and each such face
58 and 59 of triangle 50 has three groups of facets therein. For
example, face 56 has groups 60, 61 and 62, and face 58 has groups
63, 64 and 65 molded thereinto. Groups 60 and 61 and groups 63 and
64 are each analogous in properties to groups 24 and 25 of portion
21 of body 15, groups 62 and 65 are each analogous in properties to
group 23 of portion 21 of body 15.
In FIG. 6 is shown another embodiment designated in its entirety by
the numeral 67. Body 67 is adapted for use as a sign post or
directive arrow combination. Construction of body 67 can be similar
to that used for body 15.
In FIG. 7 is shown another embodiment designated in its entirety by
the numeral 68. Body 68, like body 48, is suitable for use on a
bicycle or the like. Construction can be similar to that used for
body 15.
In FIG. 8 is shown an embodiment designated in its entirety by the
numeral 69 which is similar to body 68 except that here a rod 70 is
extended through the members 71 and 72 to secure such together in
the indicated normal desired relationship. Rod 70 at its bottom end
is fitted, as by crimping, threading, or the like, with a yoke 73
adapted for mounting body 69 to a frame member (not shown), such as
a bicycle basket, handlebar, fender, axle shaft, or the like. The
upper end of rod 70 is threaded and fitted with washer 74 and nut
75 for clamping the entire body 69 together.
In FIG. 9 is shown an embodiment which is designated in its
entirety by the numeral 77. Each of the reflectorized subassemblies
78 and 79 of body 77 can be constructed analogously to subassembly
31 of body 15. The subassemblies are adapted to be mounted in
vertically spaced relationship to each other, as illustrated, by
means of a core bar 80 which extends internally through diagonal
corner portions of respective diamond shaped subassemblies 78 and
79, subassembly 78 being fitted with a socket internally (not
shown) in its upper corner 81. In manufacture, it is convenient to
seal the halves of each subassembly 78 and 79 around bar 80.
In FIG. 10 is shown an embodiment which is designated in its
entirety by the numeral 83. Body 83 is similar to body 77 except
that in body 83 subassembly 84 is not only vertically spaced from
subassembly 85 but is additionally horizontally translated in
relation thereto. (although the lower left hand corner of
subassembly 84 is spatially positioned immediately above the right
hand corner of subassembly 85, as shown in FIG. 10). Body 83 is
useful with an obstruction such as wall member 86 that interfere
with the normal reflective function of subassembly such as 84. Body
77 has a similar utility.
The interrelationship between a group of facets in a
retro-reflective reflector which is adapted to retro-reflect at an
angle of .+-. 30.degree. in one direction compared to a group of
facets in such reflector adapted to retro-reflect at a side angle
of up to about .+-. 45.degree. is illustrative by FIGS. 11 through
19. In th manufacture of retro-reflective reflectors of the type
used in the present invention a plurality of so-called pins 150 may
be employed. Each pin, as shown here, is hexagonally shaped. The
transverse distance B between flat sides is variable, but is
typically of the order of about 0.094 inches while distance A
between opposing sides is similarly variable, but is typically
about 0.108 inches. Three intersecting facets 151, 152 and 153 are
formed at the forward end of each pin 150. Each facet 151, 152 and
153 traverses two sides of the hexagonal pin and has an apex
coinciding with the axis 154 of each pin 150. Each facet has an
angle relative to the axis of about 35 1/4.degree..
The pins are arranged into a pattern, such as shown in FIG. 12, and
an electroform mold, or the like, is made using such pin pattern,
the electroform being concurrently made by electroplating nickel or
the like onto and over a plurality of aligned pin 151 heads. In
such process the high points are reversed in mirror image fashion
in the product mold (over the former low points in the pins) and
vice versa, all as those skilled in the art will appreciate. From
the product mold, a reflector element is molded. A section of the
resulting reflector is shown in FIG. 13. When a reflector body
having a plurality of individual facets, such as those shown in
FIG. 13, is caused to retro-reflect incident light, a
characteristic pattern of reflected light results, in solid line
form shown by an isocandle per foot candle curve in polar
coordinates. When the facets of FIG. 12 are rotated through
180.degree., a similar characteristic pattern as shown by the
dotted line in FIG. 14 is produced. However, when one tilts the
axis 154 of each of a plurality of pins 151 arranged in a pattern
such as shown in FIG. 12 from the vertical position shown in FIGS.
11-13, through increasing angles of common inclination, there is
produced a changing family of characteristic patterns of reflected
light, such as shown in FIG. 15, each succeeding plot 156, 157, and
158 representing an isocandle per foot candle curve in polar
coordinates, each curve representing a greater inclination angle
for a group of pins, which are electro formed into a mold, and then
the mold used to make a reflector body. The plots of FIGS. 14 and
15 are not for any specific reflectors, but only are given herein
to illustrate the principles involved, which are known already to
those skilled in the art.
When one tilts the axes 154 of such a plurality of such pins 151 in
the opposite direction, then is produced a changing family of
characteristic curves like those in FIG. 15, but reversed.
When one combines into a single reflector body both the type of
composite reflex reflectance shown in FIG. 14 with the type shown
in FIG. 15, and, in addition, uses two standard sections such as
shown in FIG. 12 but with each section oriented 180.degree. with
respect to the other, there is produced in a single reflector body
both such types of reflect reflectance, that shown in FIG. 14
sometimes being known as a "standard" reflector having a
characteristic reflectance value generally given as .+-.
30.degree., that shown in FIG. 15 sometimes being known as a "wide
angle" reflector having a characteristic reflectance value which
can range very widely from about 10.degree. to 88.degree., though
values between about 25.degree. and 70.degree. are particularly and
preferably useful. Such a combination reflector body displays a
plot of retro-reflectance angle versus reflected light intensity as
shown in FIG. 16, lines 159, 160, and 161. Line 160 is produced by
the so-called standard retro-reflector facets, line 159 is produced
by the so-called wide angle retro-reflective facets sensitive to
light on the right side of the ordinate 162, and line 161 is
produced by the so-called wide angle retro-reflective facets
sensitive to light on the left side of the ordinate 162.
If, for example, the number of standard facets is increased, the
amount of reflected light increases (see dotted line 163). If, for
example, both the number of wide angle facets and their respective
angles of inclination are increased for both right and left hand
members, the dotted lines 164 and 165 result. United States
government federal standards for a bicycle reflector comprising
such a combination of left and right wide angle reflector groups in
combination with a centrally viewable standard reflector are shown
in the illustrative plot of FIG. 17. By combining different pin
groupings at different respective facet axis angles one can produce
an unlimited gradation of retro-reflectance characteristics in a
given retro-reflector, so that any given reflector can be produced
by one skilled in the art within the limitations of pins, materials
of construction, design standards, and the like, using known
technology.
Other and further embodiments and variations of the present
invention will become apparent to those skilled in the art from a
reading of the present specification taken together with the
drawings and no undue limitations are to be inferred or implied
from the present disclosure.
* * * * *