Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS2910792 A
Publication typeGrant
Publication dateNov 3, 1959
Filing dateOct 6, 1958
Priority dateOct 6, 1958
Publication numberUS 2910792 A, US 2910792A, US-A-2910792, US2910792 A, US2910792A
InventorsJr Henry C Pfaff
Original AssigneePfaff & Kendall
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Highway sign
US 2910792 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

Nov. 3, 1959 H. c. PFAFF, JR

HIGHWAY SIGN 2 Sheets-Sheet 1 Filed 001'.. 6. 1958 ATTO R N EY Cf PAM; JH.

Nov. 3, 1959 H. c. PFAFF, JR 2,910,792

HIGHWAY SIGN Filed Oct. e. 1958 2 sheets-sheet 2 /b/aMA-V ATTORNEY United States Patent 4l() HIGHWAY SIGN Henry C. Pfaff, Jr., Summit, NJ., assignor to Pfaff and Kendall, Newark, NJ., a corporation of New Jersey Application October 6, 1958Serial No. 765,652

3 Claims. (Cl. 40-130) Directional and other signs are relied upon for the efficient and safe use of high speed turnpikes, parkways `and other roads which are engineered, and used in reliance thereon. One of the more popular types of signs in use on such highways is the luminescent sign which, by virtue of the soft glow and sharp definition thereof is easily read, and which is becoming increasingly more popular for highway use. Such signs are electrically illuminated at night, usually through the use of alternating or high frequency current, which excites luminescent metallic particles such as, for example, phosphor, to make the same electrically luminescent. The sign thus electrically energized in darkness, is readily visible; the luminescent material containing paint or body of the sign characters are equally readable during daylight hours.

The hazard, however, of such signs in highway use is the possibility of failure of electric current due to power failure, short circuiting and other causes. Such signs then become wholly inoperative in the dark, with ensuing hazard to motorists.

The device of the present invention provides a completely reliable, operative highway sign having means for continuing projection of the sign message notwithstanding power failure. Thus the present invention, recognizes the problem and provides a completely reliable solution, in a novel manner described below and shown in the accompanying drawings wherein,

Fig. 1 is a partly fragmentary, elevational view of a sign embodying the invention,

Fig. 2 is an enlarged end elevational view of another form thereof.

Fig. 3 is a fragmentary elevational view of the sign, showing one of the letters formed thereon pursuant to the invention,

Figs. 4 and 5 are enlarged, sectional views of two forms of the invention, taken at line 5 5 of Fig. 3,

Fig. 6 is a fragmentary, enlarged perspective View of one of the letters of the sign embodying the invention,

Fig. 7 is an enlarged, sectional view taken at lines 5-5 of Fig. 3 of another form of the invention,

Fig. 8 is a fragmentary elevational view of another form of sign embodying the invention, and

Fig. 9 is an enlarged schematic vertical sectional view of a sign embodying the invention, indicating, schematically, light rays projected onto the sign from the headlights of approaching vehicle and reflected pursuant to the invention.

The invention is especially concerned with the sign message elements 12 and their construction pursuant to the invention so that if not electrically energized as they should be after darkness, the message therein will nevertheless be projected in luminescence to oncoming vehicles, continuing functioning of the sign pursuant to the invention notwithstanding power failure.

The drawings are exemplary of several forms of the invention-it being understood that the invention may be embodied in other forms, as will become apparent from the description herein. Such other forms, coming within Patented Nov. 3, 1959 ICC the scope of the appended claims, shall be deemed to be i within the spirit and purview of the invention.

The invention may be applied to a sign of any configuration as, for example, shown in Fig. 1, wherein the sign comprises a background panel 13 which may if desired be painted in an opaque color or contrasting color to that of the message units 12, which are suitably secured thereto as, for example, by means 14 shown in Fig. 2. The units 12 are preformed of the outline desired and arranged on the sign in message-spelling sequence. The sign is disposed in overhead relation to approaching motorists, being secured to a post 15 (Fig. 2) or to overhead supports 16 and 17 (Fig. 1) positioned along the highway, in the range of light (11, Fig. 9) projected from head lights (10) of oncoming vehicles. The sign may be connected to a suitable power source, as for example, by the cable 18 (Fig. l) which the message units 12 may be suitably connected toas schematically noted at 19, Fig. 6. The specific form of panel and supports 13, 15, 16, 17 in Figs. l and 2 and bar panel 20, Fig. 9, and its support 15 are shown as illustrative only, the invention not being limited thereto.

The message units 12 may comprise (Fig. 4) a base sheet 21 which may be of metal or other material cut or otherwise formed to the outline desired, to which a luminescent material containing layer 22 which may be of a ceramic or vitreous material is secured as by baking or firing, or otherwise adhering the same thereto, or as shown in Fig. 5, by use of an intervening adhesive layer 23. The layer 22 may comprise a portion 22a formed as above noted of vitreous material containing the luminescent particles which, when energized, become luminescent, as for example, when excited by the use of alternating or high frequency current carried by cable 18 with which the message units 12 are suitably connected as by electrical connection of a conducting portion 2217 (Fig. 5) separately formed or combined with luminescent material containing layer 22a, terminals 19 being connected with said electrical conducting portion.

Pursuant to the invention, light reflecting members 30 (which may be in the form of a plurality of beads of very small size having a high index of reflection) are secured to the luminescent material containing layer 22, as for example, by embedding or fixing said light reflecting members 36 (Fig. 5) in a plastic or other transparent or translucent light permeable conductingl layer of material 31, secured to layer 22, also sealing the luminescent material containing layer 22 from the elements and which may serve as the other current conductor.. The light refleeting members 3d may be embedded partially in the luminescent material containing layer 22 as shown in Fig. 4 and a final light permeable coat layer 32 applied thereover, or, if desired, as in Figs. 5 and 9,. the outermost light permeable layer 32 may contain the light reflecting members 30 or a second layer thereof.

Pursuant to the invention, when the elements 12 are electrically energized, luminescent light rays of the outline of the message unit l2 (as indicated at 33 in Fig. 7) will be projected from the electrically energized luminescent material containing layer 22. If, however, said luminescent material containing layer 22 is not electrically energized, then the light rays 11 (Fig. 9) of headlights l() of oncoming vehicles in the evening, projected onto the sign, striking the light reflecting members 30, will be reflected back as rays schematically shown. at 34 in Fig. 9. Thus the sign will be illuminated and will continue to convey the sign message notwithstanding power failure. ln the form shown in Figs. 8 and 9 the light message elements l2a may have the luminescent material containing layer 22 molded or otherwise formed cast as a unitary complete message instead of as separate units 12 as in Fig. l; the self-contained unit of Fig. 8 is not dependent on or secured to a base member 21 and may be secured to a panel or bar 20 by bolt or other means (not shown) with opaque material 3S covering the spaces intermediate the message elements 12a.

The elementV 12 may be provided with a painted marginal border 24, Fig. 3,` for further daylight definition. The light reecting elements 30 may be incorporated (Fig.v 5) continuously on intermittently in material containing layer 22 or coating 32 therefor, in single (Fig. 5) or multiple (Fig. 9) row arrangement.

The luminescent material containing layer 22 (Figs. 3, 7, 9) or 22a (Fig. 5') may be opaque and may be of a ceramic or vitreous material. The light rellecting members 30preferablyA are of a high index of light reflection. By controlling. the quantity of said members 30 covering a given area of the luminescent material containing layer, the intensity or brightness of reflection of light may be controlled.

From the drawings and above description it will be noted that the invention consists in the provision of light members sensitive to an electric field, and an alternating electric eld such as an alternating or high frequency current source to activate said light members for the emission of fluorescent light as a normal procedure on turning on the current, plus light-reilecting members in` corporated therewith in the elements 12 to continue display of the message to oncoming vehicles by reflection of their headlightfbeams, in the event of power failure of the sign. The specific form of the message elements 12 and the means for securing or displaying them may be varied; the examples in the above specification and drawing are illustrative only. For example, elements 12 might be yin the fashion of a printed circuit or of outline rather than solid form and might be in the form of a solid panel wherein the elements are dened by opaquely painting the remainder of the panel to outline the elements to be displayed. Such and other forms of the elements may embody the invention as defined in the appended claims.

Having thus described my invention, what I claim asl new and desire to secure by Letters Patent is:

1. A sign for connection to an electrical power source and for display along a highway in the range of light projected by headlights of oncoming vehicles, said sign comprising electrically-actuated message elements, juxtaposed on a background panel in message-spelling sequence, each element comprising a luminescent material containing layer formed of an insulating portion and a conducting portion adapted to be connected to the powerv source and being preformed of the outline of the` message element to be displayed, so that a body of luminescent light of said outline will be projected from said element when said layer is electrically energized to luminescence, and a light permeable layer carrying on said luminescent material containing layer light-reflecting beads having a high index of refraction to reect light projected thereon oy oncoming vehicles approaching the sign, so that, when said luminescent material containing layer is electrically energized, it will project luminescent light of said outline and, when not electrically energized, the beads will reflect light projected thereon by oncoming vehicles, so that the intended message will be conveyed to the operators of such vehicles when approaching the sign in the dark, whether or not the sign is electrically energized.

2. A sign as set forth in claim l, wherein said lightrelleeting beads are partially embedded in and ,extend from the light permeable layer.

3. A sign as set forth in claim l, wherein there is a second light-permeable layer positioned over and sealing the first-mentioned light-permeable layer and the lightreecting beads.

Nikonow Mar. 1, 1932 Rolph Dec. 21, 1937

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1847134 *Feb 21, 1931Mar 1, 1932Nikonow John PTail lamp
US2102975 *Oct 31, 1934Dec 21, 1937Holophane Co IncVisible signal
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3176420 *Oct 31, 1962Apr 6, 1965Alverson Howard CReflex sign
US3510976 *Mar 20, 1968May 12, 1970Prismo Safety CorpSafety road sign
US3780462 *Oct 20, 1972Dec 25, 1973Canrad Precision IndLuminous indicators involving phosphors
US3890054 *Apr 1, 1974Jun 17, 1975Connor Sean E OFlexible highway marker
US4250646 *May 21, 1979Feb 17, 1981Trachtenberg Samuel ZHighway sign
US4622623 *Mar 5, 1985Nov 11, 1986Officine Panerai S.R.L.Luminous signalling plate, particularly suitable for the installation on the deck of a ship
US4715137 *Jan 31, 1986Dec 29, 1987Scheve William JIlluminated display with beaded light-transmitting image
US4726134 *Nov 21, 1986Feb 23, 1988Minnesota Mining And Manufacturing CompanyRoadway sign
US5237448 *May 26, 1992Aug 17, 1993American Ingenuity, Inc.Visibility enhancing material
US5243457 *May 26, 1992Sep 7, 1993American Ingenuity, Inc.Material with enhanced visibility characteristics
US5300783 *Sep 30, 1992Apr 5, 1994American Ingenuity, Inc.Layered reflecting and luminous material
US5303492 *Oct 21, 1992Apr 19, 1994Dan NishioRetroflective road sign having translucent border around legend segments
US5315491 *Feb 17, 1993May 24, 1994American Ingenuity, Inc.Reflecting and luminous layered material
US5452532 *Sep 24, 1993Sep 26, 1995Nishio; DanCustomizable sign having translucent border around retroreflective message
US5966855 *Dec 16, 1997Oct 19, 1999Miner; Race K.Cryophotonic back-lit sign
US6166856 *Jun 15, 1998Dec 26, 20003M Innovative Properties CompanySelf light-emitting retroreflective sheet and method for producing the same
US6237266Jul 11, 1997May 29, 2001Daniel J. TasseyEvacuation route having photoluminescent indicators
US7543954Sep 15, 2004Jun 9, 2009World Properties, Inc.Large area EL lamp
US20140043787 *Aug 8, 2012Feb 13, 2014Wei-Kung WangLamp to enhance photosynthesis and pest control and an oxygen generator having the same
WO1998058281A1 *Jun 15, 1998Dec 23, 1998Minnesota Mining & MfgSelf light-emitting retroreflective sheet and method for producing the same
U.S. Classification40/582, 362/812, 40/542, 362/84
International ClassificationG09F13/16
Cooperative ClassificationY10S362/812, G09F13/16
European ClassificationG09F13/16