US2367067A - Reflector - Google Patents

Description

Jan. 9, 1945. l Q sPlETH 2,367,067

REFLECTOR Filed Dec. 12, 1940 215 -213 216 Yl l l.

theesign' eaolp including; afxvnmber Patented Jan. 9, 1945 rlJ=l5Ir15EDi PA'l?"ENT OFFICE astma? f REEBEGTORf. William-asma@ cieveianain'eiglitseoliia Applies-nemo@number-12, 1940;;srit-11Ntcseagate ,sometimew (orcs-82)? This vfinventiorrrelates--tty-av1 lightffreectingwd'evice'.L and* isf particularly adapted' fr viisein signs-,i markers;I and".siirliline` devices; Wlf'iicliare intended:y toe-receivek light fromf the lamps oiet arrV oli-cominga I vehicle-f' orrth'ealikelanditoeretum this llight tetherr driver.;

Anobjectfofftheinvention i's-toprovide an im:v` proved-" reflector havin'ghigh visi-bility.I

Another 'l object-*isl to provideeanf improved re^- flct'orv W'heh'; will? return' light? directeiil toward ittthroughoi-xt an;extremely:extensivefzonei Another object-a isv` to" provide an) improved reflector which WillE beAN relatively-AAH immune1 to@v breakage-s. v

Another:y objectlffis to provider an'i improved i ree# ec-tOri-ini which thee'partsmay" befassembled atil y normalatmospheric?temperatures? Another object is to provide anfimprovediree ector J which: may:y b'ee easily an'd eoonomiea'lly manu-factred'- l y f 7 Anoi'lher-- object.. isi` toprovidei anf improved-"P ree fieot'or. wliiohwill notzbef subjctfto deinri'or'atirmav from vexposure'to the weather. i

Another. ob'jeotv isitoprovide auf improvedzlire;V fleotorrwl'iioh fmay -bef readilytassembldinto' sign-s; markersgiandthefli-ke;

Anotherf'ohjectlis tomrovide:A an "improvedlfre at andattraotiveeinape pearan'oe Gtherl-robjectss williherein'aft'erf appear? The inventiorriwilllbe better! miniers-toed-frorriiv the description of severairpraetcaiemtiodimentsf thereof, l-lustratediintheaecompanwindrawing; inwhich; f f` Figure liis'ia frontselevationailviemof aisign, such asA may `be used for.'displaying:trier-streetf numberrofi a-z building; thelvarious-:ioharactersf 'of f'of i reflectors 1 embodyingsthe invention; f l

Eigur'e '2f' is' an; enifrgedf sectional somewhatVj diagrammatimview' `of itheelerIs-:and n reflctbrjporh' f tien offthe device,

Figu're'- 3Z is anenlargedelevational viewof .on'e of the charactersof theisign of Figurel;

` ponent'parts makingguptthe.IcharactertofiFigure2 v in disassembled relation.;

FPi-gure'..issaviewfof, the .parts .ofFigura x3 FigureB, offthree"otherm'odioations emb'odfing; the invention; i

FigureA 9W" isf ai View f similar" to Figur'ei 4i of an: otherfembod'iinent of thef'i'nvention, showing tli'e partsiin disassembled' relation; and= parts -of` Figure 9 in assembled yrelation;

Reectors are used extensively' for" various kinds'f'ofisignsfand similardevicesgsuch as hihvertising signs; asfsafety'devicesionvehicles; and the lik'e.

posed i ofi" a number-f' ofiA small?" separate oi'cu1ar,

prismaticf,` oroth'erisliapedfreectors. y

They? also* haverbeeiiy composed' of? a" numberl ofnaterials suohas' in their simplestl'formgbeingi'" merely; sheet? metalf'providd with' af r'eectiii'g"=`r surfacei Which'-A mayi orf' mayfnot becolored; and

ini otherfformseconsistingfof 'glass' plates; prisms;k andith'e like; provided with:- reeotir'ig ooatingsf sucl'vl. as* of Quicksilver; with" metallic' reect'er's-i placed behii'id'them:

'orfiniwhich'theyareformed.

With exposure to theweathenlhowever;they* Abeco'n'ie-idim inxltime. Thisis due; doubtless; to

thecorr'o'sion ortarnisriingoftherefictor'mare-- are; off cou-rse; exposed: ful-Iy: to' th'e weather.

them@l sof-thatit: may' .Workuini aroundthef edges andfinftimef destroy th'eirfreflectirrgisurfaces: Moreover: asw a-bovezpointedioutf ail'1 prior-:frei- A`fieotors .arefeffctve L, only:In through. as relatively?V limited: angle, being-' most visible` whenl light isi. thrown on them in a direction normal to their."

180r extentihin i all) directionsfr. asfithe opticah All? prior'r reectors With which Tanti` familiarz" are` possessedfoff certain' inherent disadvantages? ,-When'vnew, theyfgenerallyi.renecelight firly: W911i DIOVidigfte light? comes frornn'early nora l 36 malv toi the suriaeei to which theyf are attachedr WhenY simple metal reflectors are used; ythey' characteristics of the reflector do not vary as the position of the light and observer move throughout this zone.

This will be better understood by a reference to the diagrammatic illustration of Figure 2,

In this figure is illustrated a transparent lens, indicated generally at I, which lens consists of two concentric spherical surfaces 2 and 3, each extending throughout a' spherical zone of one hemisphere, the surfaces being joined by a plane surface 4. The surface 3 is provided with a reflector or speculum shown as a hemispherical metal cup 5, which fits closely against this surface.

If, now, a beam of light, consisting of parallel rays Ba, 6b, and 6c be considered as approaching the reflector from any direction, it will be noted that this beam impinges on spherical surface 2 in such a manner that one ray 6a strikes the surface of the lens' exactly normal toits surface and that rays 6b and 6c, equally distant therefrom, strike this surface at a relatively slight angle from the normal. Ray 6a,ltherefore, is not deflected in any manner from its course, but continues straight through the lens to the speculum 5, being normal to this surface, and

is reflected back along the same line on which it approached the reflector.

Rays 6b and 6c, however, are refracted slightlyl toward the path of ray 6a, strike the speculum at a slightly oblique angle, so that when returning to the outer air, they are refracted to be somewhat convergent, as indicated by the arrowheads applied to ray 6b.

If the radii of surfaces 2 and 3 were such that the speculum 5 lay exactly at the focal distance from the surface 2, the rays would all focus at one point and return substantially along the paths they had followed in reaching the reflector.

I ilnd that this arrangement gives a very brilliant spot oflight of very minute size. its brilliancy is visible only with the eye substantially in alignment with the source of light.-

While such an arrangement would present doubtless the maximum elllciency, it is impracticable for the purpose for which the reflector-is intended, in that these reflectors are mainly 0bserved by drivers of vehicles, the drivers eye being substantially above and generally somewhat to the side of the source of illumination, namely, the cars headlights.

I flnd, therefore, thatthe surface 3 mustbe one defined by a radius greater than that of surface 2, but less than that to the focal distance which would be dened by the surface 2.

In using for the transparent material of the lens, the transparent plastic known as Lucite,

. or with glass, I nd that the radius of surface 2 should be approximately 3%; the radius of surface 3.

This ratio would doubtless vary somewhat with the index of refraction of the transparent material used, but this proportion seems to be satis- Also l have shown a number of possible embodiments of the invention.

Figures 1, 3, 4, 5, and 6 show one manner in which it may be applied.

Inthese ilgures is shown a series of numerals such as may be used for a street number sign, to be placed before a building, and, as illustrated, the sign consists of four panels (1, 8, 9, and Ill) mounted in a rectangular frame I I, which carries at the top a single large circular reflector I2.

On the face of each panel is delineated a numeral consisting of a projecting body provided with a number of circular reflector buttons, the

projecting body of the panel 1 carrying the numeral 1 being the one chosen for illustration in the succeeding figures.

'I'he panel itself is shown as a small rectangular piece of flat material, such as sheet metal,

being cut through to provide an opening substantially the shape of the character to be applied.

This numeral is outlined by means of a body portion I3 provided with a plurality of circular apertures I4 in which are mounted the reflector lenses, Visible from the front of the sign. A backing or. covering block is arranged to secure these reflector lenses in place and to clamp the body I3 to the panel 1 as well as to seal between itself and the body the specula for the several reilecting elements, as will be hereinafter described.

The body I3 has shoulders I5 adapted to rest upon the front face of the panel 1, and within these shoulders is a flange I6 which projects through the opening in the panel.

The lens consists of a piece of transparent `material having a vspherical surface 2 of smaller radius and a spherical surface 3 .of larger radius, corresponding to those described in conjunction with the diagram.

The two spherical surfaces are connected by a stepped surface, providing a recess I1 and a flange I8, which are arranged to interlock closely with a flange I9 and recess 20, respectively, formed on the inner side of the body I3. The speculum is a hemispherical metal cup 5, which,

as'above indicated, has a highly reilective inner surface.

The speculum may conveniently be a stamping made from suitable sheet metal.

v The backing block 2| is provided with a hemispherical recess 22 to receive the speculum and with'a groove 23, which constitutes a mortise capable of receiving flange I6 in the manner of a tenon, to hold the parts together.

Outwardly beyond this recess, a flange 24 is arranged to bear upon the rear side of panel 1.

These parts are assembled as most clearly shown in Figuresfl, 5, and 6.

While, of course, I may use any satisfactory transparent material for the lens, and the same or any other material for the body I3 and block 2I, I prefer to make these parts of molded plastic, and preferably of the same or similar plastic. If they be made of such material they may be permanently united by means of either a cement or solvent.

First positioning these parts as illustrated in Figure 4, the interlocking surfaces of body I3, block 2l, and the recess I1 and flange I8 of the lens are coated with a suitable adhesive or suitable solvent, the parts pressed together into the position illustrated in Figure 5, and held for a short time until the cement hardens or the solvent evaporates.

With materials which may be united by solvent, the contacting surfaces of these materials, in effect, fuse into each other, so that upon complehesive or solvent, and so likewise seals lustrated in Figure 6, in which the body, lens, and

backing block have become a single integral block of material, completely encasing the speculum and clamping itself to the panel I so that it may not be removed therefrom without destructionr or deformation of either the block ofk material or the panel.

The speculum, being thus encased, is absolutely sealed away from the weather, moisture and the like, and protected against deterioration so lontr as the encasing block remains unbroken. Its useful life as a reflector is therefore innite. It will also be noted, that no heat need be applied, and discoloration which might take place if the transparent material were molded about the metal is thus avoided.

In thecase of the single reflector I2, shown on the sign, the body and backing block are circular, the body being indicated at I3a, but it will be appreciated that the cross-section of the parts of this reflector will be identical, wherever the section is taken, to the illustrations 4, 5, and B,`and

also, that the numerals themselves might be formed of single reflectors made in this manner.

Figure 7 shows a modification in which the supporting panel and backing block are made integrally in a single piece of molded plastic ma- Y f terial or the like, indicated generally at I01,.and

provided on one face with hemispherical recesses |22 and with mortise-like recesses I23 which re'-y vceive the depending flange IIB of blocks II3.

The lens used in this structure is substantially identical to that above described, having spherical surfaces |02 and I03, and a hemispherical speculum |05. It will be appreciated that the body l I3 is, as in the first embodiment, sealed to the backing body and panel by means of a suitable adin the speculum.

In Figure 8, the backing block 22| is provided with recesses 223 to receive the flange 2I6 of the the lens so that they totally enclose the speculum 205. I

These parts are adapted to be mounted in a wooden panel 201, the backing block fitting into a recess cut into this panel and the entry of the entire character being limited by the shoulders 2I5 which rest upon the front face of the panel. The space within the panel and about the backing block is, filled with a suitable cement or adhesive material 2I0, such for instance, as the cellulosek composition now known as .plastic wood, to retain the character firmly in place.`

In Figures 9 and 10, still another embodiment of the invention is illustrated, in which the reflector consists of only 3 parts, the lens, the backingblock and the speculum. f

Here again, the radius of the exposed surface of the lens 302 is related to the radius of the reflector surface 303 in a ratio such as disclosed in conjunction with the diagram of Figure 2. Y

The backing block 32| has spaced annular flanges 323 and 324 between which is received an annular flange 308 formed integrally with the lens and by which the parts are sealed together. The lens has a peripheral flange 3|5 formed integrally therewith, between which and the kilange 32-4 the edges of the panel 301 may be gripped.

While the specula shown are each approximately a hemisphere, it will be apparent that they could be limited to a Zone somewhat less in extent, which will correspondingly' limit the angle through which the maximum brilliance cf the device is observable, particularly when the reflectors lare to be used in places where it is not desired that the reflected light be seen through a wide angle. The angle through which it may best be seen will be approximately that defined by the speculum and thus readily may be deter.

- ulum.

While I find that the transparent plastics produce a particularly suitable reflector which is unbreakable, and which is not seriously impaired by surface scratches or the like, it will be apbody 2|3, these two being sealed together and to parent that the lens portion of the device may well be made of any transparent material such as glass, and that with such a material, the parts would be secured to this material by adhesion rather than by fusing with the glass itself. However, adhesive on the interlocking flanges shown produces a very effective seal and adequately protects the speculum.

While I have described the illustrated embodiments of my invention with some particularity, obviously many other modifications and variations will readily occur to those skilled in the art to which they appertain. I do not therefore limit myself to the rprecise details shown and described, but claim as my invention all embodiments, modications and variations within the scope of the appendedclaims.`

I claim:

1. A reflector comprising a lens defined by two concentric spherical-zone surfaces of different radii, a spherical-zone shaped speculum adjacent the surface of the lens of larger radius, a back f block receiving said speculum, a body having an aperture through which the spherical zone of smaller radius of the lens projects, intertting projections between the body and the block, and securing means sealing the body to the block and the body to the lens.

2. A reector comprising a lens dened by two concentric spherical-zone surfaces of different radii, a spherical-zone shaped speculum adjacent the surface of the lens of larger radius, a back block receiving said speculum, a body having an aperture through which the spherical zone of smaller radius of thelens projects, intertting projections between the body and the block, and securing means sealing the body to the block and the body to the lens, and a support held between the lbody and the block.

3. A reector comprising a lens defined by two concentric spherical-zone surfaces of different radii, a spherical-fzone shaped speculum adjacent the surface of the lens of` larger radius, a back block receiving said speculum, a body having an aperture through which the spherical zone of body to the lens.

WILLIAM O. SPIETI-I.

Images