US2117639A - Traffic signal - Google Patents

Description

May 17, 1938. c. B. WATSON TRAFFIC SIGNAL Filed Aug. 7, 1935 2 Sheets-Sheet l INVENTOR. C. B. WATSON.

A TTORNE Y.

Patented May PATENT OFFICE memo srcmr.

Y Charles B. W tson, Omaha, Nebn, assign'or of forty-nine pe cent to Fay G. Johnson, Omaha,

, Nebr.

.Applicationsdugust '1, 193 5, Sprlal No. 35,095

This invention has to do with the art of traffic signals for useat street intersections and the like for the control of traflic and of signals generally. The invention especially relates to traffic signals embodying the elapsed time principle in which the signal lights comprise vertical illuminable elements such as neon tubes.

Heretofore to my knowledge, all previous attempts to produce trailic lights with neon and other luminous tubes have been unsuccessful by reason of the fact that the present art affords tubes not to exceed millimeters in diameter and their position. in thestructure has been such that when exposed to sunlight, illumination produced is negligible. Another .difliculty encountered by the present art is the fading of color in such tubes in cold weather. In such weather the green color is particularly susceptible and will turn white in cold weather.

It is therefore the object of my invention to provide a traflic signal wherein the luminous elements are shaded from extraneous light to increase their visibility and color. Another. object of. my invention is to provide illuminable signal tubes of relatively great width and of great light intensity. 7

Still another object is to provide for-suitable self-heating of the tubes to keep same warm in cold weather to increase their efficiency in such Weather and to maintain their color.

A further object of my invention is to provide a positive, continuous, visual informative trafiic control signal to minimize intersection hazards, and having a threefold, instantaneous and simultaneous, visual indication showing the existing direction of trafhc, the time that has elapsed since the commencement of a particular signal, and the time that must elapse before a change of traffic direction is signalled. V

A further object is to provide a signal having a minimum number of illuminable signal elements or tubes, each element being adapted to be seen from two directions for controlling or directing trafiic from opposite directions.

Other objects are to provide an illuminant having a high atmospheric penetration characteristic in order that signals may be seen from relatively great distances; to provide a signal having a uniformly moving time indication for the psychological effect of. concentrating the attention upon the cycle of operation; to provide a signal with the above characteristics having a weatherproof head enclosing the illuminatingelea ments; to provide a signal wherein one tr'ansformer may handle sets of tubes alternately; and

3 Claims. (Cl. 177%327) hereinafter appearing when taken in conjunction with the accompanying drawings, wherein:

Figure l is a side view of my trafllc signal.

Figure 2 is an enlarged side elevation of the signal head of my invention with the corner glass panels removed and a portion of a vertical shield broken away showing the spirally coiled neon tube behind said shield.

Figure 3 is a plan view of .the signal head. Figure 4 is a horizontal section through the signal head taken on line 4-4 of Figure 2.

Figure 5 is a plan view of a metal plate on the floor of the base of the signal head having notches for accepting the ends of the glass panels and openings for securing the tubes.

Figure 6 is an enlarged detailed partial section showing the seal between the vertical edges of the glass panels and the vertical face or side shields.

' Figure 7 ice. wiring diagram of a signal head having four tubes, each tube having end electrades anda plurality of longitudinally spaced intermediate electrodes. ,s

Figure 8 is a wiring diagram showing the wiring hook-up for a plurality of signals having synchronizing means for maintaining the signals in synchronism.

Figure 9 is .a diagrammatic view of cam operated contact switches'of the flasher or distributor.

Referring more particularly to the drawings the reference numeral lllindicates a standard of. The shields M are secured at the bottom to base I l by screws I5 and at the top to the shade cap by bolts IS in the upper ends thereof, said ends being inturned over the cap and terminate in pointed portions that angularly meet centrally of the cap.

The control of traffic is by the illuminable elements or signal lights comprising preferably neon tubes RI, GI, R2 and G2, such lights having great atmospheric penetration. The tubesare spirally coiled to increase the width of the signal and to p ovide lights of extreme brilliancy with a maxim concentration of Iumens from an illuminated signal of a given width and length.

In neon tubes the diameter of a tube largely determines its brilliancy when illuminated. A

small diameter tube is much more brilliant than alarge diameter tube when the electric current provided is substantially the same. With a small diameter tube low current apparatus may be used but with a large diameter tube .it is necessary to use high current apparatus to get brilliant v low current apparatus.

illumination of such a tube. Withlthe use of high current apparatus costs and operative difliculties increase. .By the use of coiled, small diameter tubes a brilliantly illuminable signal tube may be provided in the Signal with the use of low current apparatus and the coiling of the tube greatly increases the width of the light thus securing the efiects of a relatively large diameter tube with Signal tubes of substan-"' tially any desirable diameter may be used in the signal head.

The tubes are mounted in openings IT in an aluminum plate I8 on the floor of the base 'I I. Each tube extendsvertically in the head and substantially parallel with its respective shield I4, said shield being in front of the tube to shield it from view from that direction and to shade it from extraneous light such as sunlight. Neon tubes, as before stated, will suffer as to brilliancy in sunlight but by shading the tubes of the signal head the brilliancy of said tubes is substantially unimpaired or undiminished.

Each tube is provided with end electrodes I9 at the bottom and I9a at the top, and a plurality of longitudinally spaced intermediate electrodes 20. The electrodes are'received between out-' wardly extending vertically parallel flanges 2| of a vertical electrode contact board, said 'board being in the form of an X'in cross section'and having said flanges extending outwardly from the ends of said X shaped contact board, said board andflanges being of suitable insulating material.

The'ele'ctrode contact board is provided with spring contacts 22 adapted for electrical contact with the electrodes of the tubes, and said board is adapted to shade the tubescentrally, thereby concealing same from view from the side opposite the respective vertical shields I4. Each tube is shielded from view from the front'and rear- .relative to its respective position in the head, and

relative to-the face of each'side each tube is visible from two directions, laterally of said face, the visible sides of the tubes being at substantial right angles to the concealed sides. g

The tubes are arranged in the head with a red tube and a green tube, RI and G2, on opposite sides of the electrode contact board for signally controlling traflic flowing in opposite directions as east and west or north and south, and a head with four tubes is adapted to control traflic from four directions. The tubes are adapted to be operated in sets or pairs, one red and one green, RI and GI respectively, being-operated together in unison with each other, each of said tubes being visible only at substantial right angles relative to each other. Therefore traffic flowing in east and west directions nfay be signalled stop by the tube RI and the north and south trafli'c simultaneously signalled to proceed by the tube Electricity to energize the gas in the tubes is taken from the secondary 23 of a transformer 24 the primary 24a. of which is supplied with electric current from any suitable source such as an ordinary commercial circuit 25 carrying volts. One side 26 of the secondary 23 of the transformer is connected, through the, flasher, to the lower electrodes I9 of the tubes. The other side 21 is connected to the distributor mechanism of a flasher 28, operated by an electric motor 29, said motor being supplied with current from a suitable source such as the commercial c rcu t 25 carrying 110 volts. The flasher is provided with.

. The flasher distributing mechanism is adapted to complete the circuit to the upper electrode of one set of tubes, as RI--GI to illuminate the entire length of said tubes. As one tube is red and the other green, in' my preferred embodiment, for signalling respectively stop and proceed, cross-trafiic is thereby controlled. Then current is shorted through the second electrode from the top of each tube in the said set and the illumination in said'tubes drops the distance between the upper and second electrodes, the rest of the tube length being illuminated. The flasher progressively distributes current to the electrodes of}, said set from the top downwardly in regular orderly sequence until the last sections of the respective tubes are extinguished, whereupon the distributor switches to the other series of contacts as CR2CG2 to illuminate the other-set of tubes, leaving the first set of tubes unilluminated. The same cycle of operation prevails now-.as occurred in the first described series.

The flasher is adapted to break the primary at the moment there is a switch from one set of tubes to the other set to avoid arcing therein.

Cam CM operates the respective contacts to.

break the current to the transformer primary as the distributor operatively switches from one set of tubes to the other. Cams CI2 and CI3 operate contacts I2 and I3 controlling the current from the primary secondary 23 and cam CI5controls the motor circuit of the synchronizing means.

In operation the cams CI2, CI3, CM and CI5 cause the contacts I2, I3, I4, and I5 to close thereby completing the circuits to the synchrmnizing means and the transformer primary, and also completing the secondary circuit through one set of tubes as RIGI (left side), said cir-* lines of least resistance the closing of contacts I (left side) shunts the current at the top intermediate. electrodes 20 thereby causing the upper portions of the tubes RIG I to become extinguished. The'contactsl" to II inclusive are closed progressively from the top to the bottom and as each respective contact is closed the succeedin'g portion of the tubes is shunted out and extinguished until the entire length of the tubes is extinguished except for the bottom portions, whereupon all the contacts on the operated side of the distributor are broken and the above described operation will take place for the other or right side of the apparatus.

Referring more particularlyfto Fig. 9, which shows the distributor as though it 'were seen from the lower end, without the motor, reference numeral 3| indicates the shaft of the flasher on which are mounted the cams, here indicated as C. Rollers 32 are secured to springs 33 of contacts ii" and are operatively in contact with the cams.

The signal head is sealed against the weather by providing glass panels II in the interstices between the shields Id. The panel ends are accepted in notches 32 cut in the corners of the aluminum plate It and the abutting corner edges ll of said panels are sealed by transparent glue v or adhesive. The free vertical edges of the panels are provided with channels 34 of rubber received over said edges, a portion of said rubber channels being in intimate contact with the adjacent edges 35 of the vertical shields ll to form a seal therebetween. The glass panels provide a clear view of the tubes from the unshielded sides and also aid in reflecting away from the tubes extraneous light that may strike same.

The vertical coiling of the tubes provides ready circulation of air upwardly through the center will circulate through the tubes and'throughout the head and will maintain the tubes at a sufficiently high temperature to maintain their proper colors, prevent fading of color in said tubes and make for eflicient operation thereof.

An additional advantag'e of the spirally coiled tube is that the side margins of the coil are brighter than the central portionsdue to the fact that at-the sides a greater depth of illuminated gas is seen than at the central portions. A sharply delineated and brilliantly illuminated signal is therefore provided.

The coiled tubes are relatively flexible andare therefore not easily broken. Should a tube be broken or go out oi. order it may be removed by removal of the vertical shield I4 in front of said tube. The shield is removed by unscrewing the screw it and the bolt I6. The tube may then be withdrawn from the head through the vertical opening between the free edges of the glass panels, said opening being normally closed and sealed by the vertical shield? A new tube may be readily put in and the shield replaced.

At intersections provided with four signals, one at each corner, it is desirable to control the motors of the individual signals to maintain same in synchronism. The signal motors can be synchronized by any appropriate means commonly used for the purpose, said synchronizing means being indicated by reference numeral 36.

It is to be understood that the signal tubes'may be provided with any desired number of electrodes spaced in any suitable manner. The distributor or flasher may be placed, in an individual head for controlling or regulating the signals thereof or one distributor may be used to control a group of signal heads. It is also to be understood that the relative speed of groups of tubes may be varied relative to each other. This may be done to give preference to trafllc in certain directions over tramc from other directions.

Having thus described my invention what I claim is: 7

1. A trailc signal comprising a signal head, said head having a central vertical electrode contact board therein, vertical gaseous discharge tubes on opposite sides of said contact board, said tubes having end electrodes and intermediate electrodes all in operative association with the cont'act board, said contact board shielding each tube from view from the opposite side of the head, oppositely mounted tubes being of different color when illuminated to signal stop and proceed respectively, said tubes being adapted to be alternately illuminated, and a vertical shield for each tube, each of said shields extending parallel with the contact board and in front of its respective tube and adapted to shield said tube from view on the side opposite the electrode contact board, each of said tubes being visible only from sides substantially at right angles relative to the concealed sides thereof.

2. A traffic signal comprising a signal head, said head being provided with four sides, a central vertical electrode contact board therein, a-

vertical, spirally' coiled luminous gaseous discharge tube for each side of the head mounted in operative association with the electrode contact board, said board shielding each tube from view from the opposite side of the head for which the respective tubes are provided, oppositely mounted tubes being of different color when illuminated to signal stop and proceed respectively, a stop indicating tube for one direction and a proceed indicating tube for another direction being adapted to be operated in sets in unison with each other, each of the tubes being provided with end electrodes and longitudinally spaced intermediate electrodes, a vertical shield for each tube, each of said shields extending centrally of its respective side substantially parallel therewith and in front of its respective tube and adapted'to shield said tube from view on the side opposite the electrode contact board and to shield said tube from extraneous light, and glass in the interstices of the head between the vertical shields whereby each of said tubes will be visible only from sides substantially at right angles relative to the concealed sides thereof.

3. A trafllc signal comprising a signal head, said head being provided with four sides, a central vertical electrode contact board therein, a vertinal stop and proceed respectively, a stop indicating tube for one direction and a proceed indicating tube for another direction being adapted to be operated in sets in unison with each other, each of the tubes being provided with end electrodes and longitudinally spaced intermediate electrodes, a vertical shield for each tube, each of said shields extending centrally of its respective side substantially parallel therewith and in front of its respective tube andadapted to shield said tube from view on the side opposite the electrode contact board and to.sh.leld said tube from extraneous light, and glass in the interstices ofthe head between the vertical shields whereby each 61' said tubes will be visible only from sides substantially at right angles relative to the concealed sides thereof.

CHARLES B. WATSON.

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