US1995816A - Street traffic signal - Google Patents

Description

March 26, 1935.

c. ADLER, JR 1,995,816 STREET TRAFFIC SIGNAL Filed'Nov. 19, 1934 3 Sheets-Sheet 1 March 26, 1935.

C. ADLER, JR

STREET TRAFFIC SIGNAL 3 Sheets-Sheet? Filed Nov. 19, 1934 grvuc/wbo'r/ /farleaz//czle/xfrg 5% W, (in? SUM/May Match 26, 1935.

C. ADLER, JR

STREET TRAFFIC S IGNAL 5 Sheets-Sheei 3 Filed Nov. 19, 1934 Patented, Mar. 26, 1935 UNITED STATES PATENT OFFICE STREET mo srGmn. V 4 Charles Adler, In, Baltimore, Md.

Application November 19, 1934, Serial No. 753,773

3Cla'ims.

' The present invention relates to signals, and is useful in connection with all types of-signal systems. Primarily, however, it is adapted for pedestrian and vehicular trafllc signal systems.

The first aim of the invention is to increase or enhance the safety factor. Thus the present signal (1) gives an accentuated or imperative directive eifect, and (2) particularly accommodates itself to the needs of persons who are color blind, near-sighted and to those who, according totraillc authorities, do not show a normal alertness A further object of the invention is to provide a signal which will. be economical in thatit is possible to dispense with lamps of high wattage now employed, and to use in place of them, lamps of relatively low wattage, e. g., 15 to 25 watts. The saving obtained by municipalities as a result of. the installation of the present signal has been very substantial.

Briefly stated, the invention includes a reflector, an illuminating apparatus such as an electric lamp, and a cover glass or lens constituting the signal area. This latter member is constructed so that it will cooperate with the lamp and the reflector, permitting (1) the use of a low wattage lamp, (2) produclngan illuminated signal area visible at a considerable distance from the signal, and (3) producing-an illuminated signal area, a portion of which is sharply illuminated when the signal is viewed from a relatively short distance and at an angle. 1 That is, the signal area is illuminated and visible to pedestrians and vehicular traiiic moving in the lane toward the signal, and when pedestrians or vehicular trailic are in close proximity to the signal, and for example, must look up to observe it as at the intersection, or ad- Jacent thereto, a signal is sharply Presented. This is particularly important in connection with ayli ht i Referring to the drawings:

Figure 1 is a top elevation indicating diagrammatically and relatively the action ofthe signal.

Figure. 2 is a side elevation illustrating diagrammatically and relatively the action of the 18m Figure 3 is a rear elevation of the lens or cover glass. 1

Figure 4 is a section on the line 4-40! Figure 3.

Figure 5 is a top view in section showing in detail the operation of the signal when one form of cover glass is used.

Figure 6 is a top view in section showing in detall the operation of the signal, when another form oi cover glass is used.

Figures 7 and 8 are detailed views or the cover contrary a lamp'of 15 watts is highly eflicient glass or lens, Figure 7 being partly broken away in elevation, and Figure 8 being partly broken away'in section. v

Figure 9 is a front elevation of the complete signal, showing the housing and signal areas, and- 5 Figure 10 is a detached view of another form of cover glass or lens included in the present in vention.

Referring to the he signal is particularly useful for controlling vehicularand pedestrian traflic. It is incorporated, for example, in the usual signal housing shown in Figure 9 embodying a green or Go indication G, a yellow or "Caution" indication Y, and a red or "Stop indication R. In some installations the yellow or caution is eliminated. 1

Such signals are placed in the center of the intersection as shown in Figure 1, or at the corners of the intersection, as well understood.

Drivers of vehicles passing down the lane are able to observe and be directed by the signal (1) at a distance, i. 'e., at a point approximated by the position of the vehicle V in Figure 1, and (2) at a point at or adjacent the intersection, substantially as indicated by theposition of the vehicles V in Figure 1. Where a pedestrian or vehicle is at the position V moving toward the signal, means are provided to clearly indicate the direction of tramc at the intersection. When the driver reaches the position V and must, as is usually the case, look up at the signal, or view it at an angle or from an offset position, e. g., one side or the other, likewise positive means are provided for brilliantly and sharply illuminating a predetermined portion of the signal area. a

In addition to accomplishing these various functions, which I find are essential to safe and satisfactory traihc direction, the present invention is operative at a much greater economy than signals now in use. Present day signals employ a dilfusing lens with a highwattage lamp, for example, a lillv ratt lamp. The present invention does not require high wattage lamps, but on the and lamps up to 25 watts may be used. The signal has been installed in various communities and in several States, and has effected a considerable saving as well as proven its enhanced value as a direction means. 50

Referring to Figures 5 and 6, the signal shown in Figure 9 willhave one or more signal elements indicated as a whole at 10-. These signal elements comprise a reflector or mirror 11, preferably of theparabolic type; lighting apparatus,

corrugated area at C 'D'.

such as an electric lamp 12 of customary design or a lamp of the character shown and described in my United States Patent No. 1,869,725; and a cover glass or lens 13 illustrated in detail in Figures 3 and 4. The cover glass or lens is preferably concavo-convex as shown in Figure 4 and is provided with a plurality of flutes or corrugations 14 on the concave or interior side. The elongated filaments 15 of the lamp of my aforesaid patent will preferably be arranged so that they extend in parallel relation to the flutes or corrugations since they are offset relative to the focal point. This is not necessary in the case of a single filament lamp as the filament will usually be disposed at the focal point as shown in Figures 5 and 6.

In addition to the fluted area 14, the lens is provided, preferably on the concave side, with a band or area 16 composed 01 a multiplicity of prisms, as shown in Figures 3 and 4. This p'rismatic area or band in the case of the red or ,Stop cover glass 13, extends at substantially right angles to the flutes or corrugations, that is the band 16 intersects the corrugations, as shown in Figures 3 and 4, to give a barrier eflfect, as will be understood upon reference to Figures 3 and 9, where the band extends across the diameter otthe lens and divides the same into upper and lower fluted areas. This prismatic band 16 in the case of the green or Go cover glass is disposed parallel to thecorrugations 14, as shown in Figure 6, and imparts the impression of a clear lane, as will be appreciated upon reference to Figure 9 (G). In the case of the yellow or Caution signal, the prismatic band 16 is disposed diagonally, as shown in Figure 9, and dependent upon the positionof the signal with relation to the highway, the direction of the diagonal may be changed as shown in Figure 10.

Reierring to Figure 1, the flutes or corrugations 14 retract the light primarily in a horizontalplane, as indicated at A-B, and give a brilliant illumination which may be easily viewed at a considerable distance from the signal, for example, at the point V. The flutes or corrugations do not direct or refract any substantial portion of the light downwardly. However, the prismatic area retracts the light in all directions and in cooperation with the reflector and lamp, the prismatic band when viewed, for example, at a point V, below the s'ignal'and/ or at one side or the other thereof, will be sharply illuminated. In this manner, and by means of a low wattage lamp, the signal is brilliantly given at a distance, and

when viewed in close proximity, as just stated,

not only is the indication brilliant, but the bands 16 are accentuated in appearance and imperative in directive effect.

The relative horizontal spread of light pro duced by the prismatic band is indicated by the line A'B' in Figure 1, and is not visible at so great a distance as the light refracted by the corrugated area. That is, the prismatic beam is short but intense, and the spread, as will be observed, is much greater than that refracted by the corrugated area and is in all directions.

The relative spread of light in a vertical plane is illustrated in Figure 2, that of the prismatic area being indicated at CD, and that of the It will be observed that the downward spread, which is all that need be considered because of the presence of the usual deflecting hood 18 associated with each signal member 10, is greater to a very considerable extent in the case of the prismatic area over the fluted area. This is important because it assures that the prismatic area 16 will be at all times intensely illuminated and when viewed from the position V, this portion of the signal area sharply stands out to give the indication.

As stated, each color lens GY--R is concaveconvex and constructed with vertical flutes on the concave side only. These flutes reflect the parallel beams of light produced by the lamp fllament and reflected by the parabolic mirror and deflect the beam horizontally only, e. g., at an angle of about 15 on either side (see the line A-B) The fluted area 0! the lens therefore serves only to slightly fan out the beam in a horizontal plane and substantially none of thelight is deflected either up or down. That is, the light -is all directed parallel to the traffic lane and band 16, as shown in Figures 1, 3, 4, 5, 7, 8 and 9,

is horizontal, i. e., diametrical' and bisects the cover glass into upper and lower fluted or corrugated areas. This produces a very wide' horizontal and vertical beam spread, so that when trafllc is stoppedby the red indication and the vehicles pull up side by side and form several trafllc lines (see Figures 1 and 2) the vehicles in all of these lines will be within range at the beam spread. That is, the vehicles in all of the several lines, by reason of the spread in all directions of the light refracted by the prismatic area, will be within the range of the beam refracted by the prismatic area, whether the vision be in direct line with the signal, or oflset, i. e., at one side or the other.

The prismatic band 16 in the green lens is vertical and diametrical, as shown in Figures 2, 6 and 9, and parallel with the corrugations. It therefore does not produce as. great a horizontal beam spread as does the horizontally disposed red band, but does produce greater downward or vertical spread. Whenthe green indication is displayed, vehicles are moving in lanes closer to the road center, past and below the level of the signal lamp, and the vertical prismatic band produces a beam which encompasses the driver's vision until he has passed the signal.

In connection with the yellow or amber illumination Y, it is standard practice to display this indication only to the lanes in which trafllc is moving and not to traflic that has been stopped by the red, 1. e., it is displayed only when or after the green is about to be extinguished. Thus the yellow or amber is displayed Just prior to the complete transfer of right of way indication to the intersecting highway, and its purpose is to stop vehicles that have not already passed the entrance to the intersection.

The prismatic band 16 of the Caution lens Y is disposed diametrically and diagonally, as shown in Figures 2 and 9, and in detail in Figure 10. In the position shown in Figures 6 and 9, the beams are deflected downward and to the right of the signal and so as to be visible to drivers of vehicles about to pass into the intersection or about to make a right turn into the cross highway and away irom the signal. When the signal is ward the signal in a lane located over the center of the intersection, the diagonal band in the Caution or amber lens Y should slant downward at an incline of about 45 from left to right, as in Figure 9. If the signal is located on the far side of the intersection, the same result is obtained by molding the band with a downward slant of about 45 from right to left, as shown in Figure 10. In this manner the beam will be visible both to tramc proceeding down the center of the lane or which is drawn off to one side for the purpose of making a turn into the cross highway.

As pointed out, the prismatic band produces a wide beam for a relatively short distance. The remaining lens area, however, is made up of the vertical flutes and these, in combination with a parabolic reflector or mirror, project a narrower beam of great intensity in a horizontal plane which is visible for great distances, notwithstanding that a low wattage light source or electric lamp is employed.

As heretofore stated, I am. able to use lamps of from 15 to 25 watts and produce-a very efllcient signal indication, at the same time obtaining a very decided economy in operation costs.

The use of the prismatic bands in combination with the fluted areas, and with the prismatic bands in different positions for each color, as shown in Figures 2 and 9, enables the indications to be readily observed by many color blind motorists and pedestrians as well as near-sighted persons who traverse the intersection. Moreover, theprismatic bands stand out in a manner to attract and awaken the senses, so that a pedestrian or driver who is not on the alert will be safeguarded by the additional attraction of the prismatic bands arranged in their several different positions. In other words, the signal aspect is much more distinctive to everyone than the present or customary signal areas now inuse. The hands, when viewed from a distance, appear darker than the fluted areas but on the other hand when the signal is viewed from an angle or at close range, the prismatic band appears definitely brighter and stands out sharply.

It will be observed that I have provided a signal comprising a reflector, an illuminating apparatus, and a cover glass or lens wherein a beam of considerable length displaying brilliantly the entire signal area is given to trafllc moving toto which the signal is presented. This beam covers substantially the entire width of the lane. Also, I have provided a signal wherein the signal area viewed at close range is translated into a brilliant indication appearing as a sharply defined contrasting area accentuating the signal and imperative in its effect. This eflect is produced by the relatively short and intense beam of greater spread in all directions, formed by the prismatic area, which extends horizontally, vertically, or diagonally, as the case may be. It is to be borne in mind that these results are now being satisfactorily obtained by means of a low wattage lamp.

Various modifications of the invention may be resorted to, all of which are regarded as comprehended within the appended claims.

I claim:--.

1. A signal unit for street trafllc control comprising a casing having an opening, a lens or cover glass over said opening, and an electric lamp of appreciably low wattage in comparison with the high wattage standard of approximately sixty watts customarily used in such units, for illuminating the lens or cover glass, said lens or cover glass having an area thereof capable, in combination with said low wattage lamp, of refracting a relatively narrow beam of light in a horizontal plane, and another area capable, in

combination with said low wattage lamp, of refracting an appreciably wider beam of light in a horizontal and downward direction.

2. A signal unit ,for street trafllc control comprising a casing having an opening, a lens or cover glass over said opening, said lens or cover glass having a band, including a plurality of prisms, extending across the cover glass and parallel flutes on one side of said band, and an electric lamp of appreciably low wattage in comparison with the high wattage standard of approximately sixty watts customarily used in such units, said lamp disposed in said casing for 11 luminating the lens or cover glass, said lens or cover glass capable, in combination with said low wattage lamp, or retracting a relatively narrow beam of light in, a horizontal plane, and of refrae'ting an appreciably widerbeam of light in a horizontal and downward direction.

3. A signal unit for street traflic control comprising a casing having an opening, a lens or cover glass over said opening, said lens or cover glass having a band, including a plurality of prisms, extending across the cover glass and parallel flutes on each side of said band, and an electric lamp of appreciably low wattage in comparison with the high wattage standard of anproximately sixty watts customarily used in such units, said lamp disposed in said casing for illuminating the lens or cover glass, said lens or cover glass capable, in combination with said low wattage lamp, of retracting a relatively narrow beam of light in a horizontal plane, and of refracting an appreciably wider beam of light in a horizontal and downward direction.

CHARIES ADLER, JR.

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