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Publication numberUS1498184 A
Publication typeGrant
Publication dateJun 17, 1924
Filing dateMay 9, 1921
Priority dateMay 9, 1921
Publication numberUS 1498184 A, US 1498184A, US-A-1498184, US1498184 A, US1498184A
InventorsMccarthy Daniel J
Original AssigneeChicago Railway Signal And Sup
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Light signal
US 1498184 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

June 17 192,4."

. Y Y 1,498,184 D. J. MCCARTHY I LIGHT SIGNAL I Fil ed May 9 1921 2 Sheets-Shem 1 June 17 1924. 1,498,184

D. J. M CARTHY LIGHT S IGNAL Filed May 9. 1921 v 2 Sheets-Sheet 2 iw'ww Patented June 17, 192d.

@NIIED STATES 3,498,184 raranr orriea.



Application filed May 9,

To all whom it may concern Be it known that I, DANIEL J. MCCARTHY, a citizen of the United States, residing at E1 in, in the county of Kane and State of Illinois, have invented certain new and useful Improvements in Light Signals, of which the following is a specification.

The invention relates to light signals and has especial reference to signals well adapted for railways.

In railway signal systems it is usual to install three indication signal units in a sin le casing and to secure the three units rigi ly in the casing and, in location where it is desirable to have the light field of one unit extend laterally beyond that of either of the other units so that the particular indication can be seen a longer distance than that of the other units, the light is extended by use of what are called spread light lenses or when lenses are used that are capable of producing a more intense beam of light, when the lamp is located at the focal point of the lens, the lamp is adjusted to a point between the focal point of the lens with which it is associated and the lens. Either of these, expedients causes divergence or spreading out of the light rays, but materially decreases the intensity of the light and the eficiency of the signal.

When a three indication si cated to project a signal indicatlon along a curve the rays of light from one unit is adjusted by rotating the pole upon which the three indication signal casing is supported, so that the light of the unit will cover a certain portion of the curve; therefore the light from the other units will cover substantially the same portion of the curve and they are all observable at about the same time from an approaching train.

It frequently occurs in train operation, in the ractice, that it is advantageous and desira le to have the engineer of the train pick up one indication in a certain part of the curve before the succeeding indication need become visible, as for example the danger signal should be the first to be seen, when approaching a curve, therefore the unit giving the danger indication should be separately adjustable with respect to the other units of the signal, so that the beam of light may be projected further from the source than that of the sequentially following beams. After the red or danger indicaal is 10-- 1921. Serial N0. 468,123.

tion, the next unit should be adjusted so that the yellow indication, signifying caut1on, w1ll follow, and finally the green indication, or clear signal, will then appear. In my 1mproved device the objection to the standard signals heretofore enumerated are overcome, and the improved results may be obtained without reducing the dens ty of the lightbeams or decreasing the efficlency of thesi nals.

By the use o my invention each of the signal unlts n a given casing is independently and universally adjustable, so that the beam of light emanating therefrom may be projected into a field not occupied or to be occupied by the light from either of the other associated signal units.

In the accompanying drawings Flg. 1 is a front elevation of a three indication signal. i

Fig. 2 is a central section thru the casing taken substantially on line 22 of Fig. 1.

Fig. 3 is an enlarged transverse section taken substantially on line 3-3 of Fig. 2.

' Fig. 4 is a section taken substantially on line H of Fig. 3 showing the signal unit in elevation.

Fig. 5 is a diagrammatic representation of the light from a signal projected on a straight piece of track.

Flg. 6 is a diagram of the three fields of light from the three indication signal device as they appear on a curve from my improved si nal structure.

In all t e views the same reference characters are employed to indicate similar parts.

The greatest intensity of the light beam, along any oint of a line projected from a given slgna is when the rays of light are in arallel lines and any departure from a eam of this character either decreases the intensity of light at any point or concentrates the light at a articular point, and in either event the e ciency of the signal for railway purposes is decreased.

In Figs. 1 and 2 a three-indication signal casing 10 is shown in elevation having a socket 11 by which it is mounted upon a pole and secured in position by the screws 13.

The casing is provided with three glass closures 14, 15 and 16, each secured in a proper frame 17. In the rear of the casing is a closure or door 18 hinged at 19 and provided with a locking device 20. The casing along the curve 36 of a railroad track, the

is of the usual form for three indication signals and contains three like signal indication units 21, 22 and 23. These units are more specifically shown and described in my copending application 'Ser. No. 465,143, filed April 28, 1921.

The casing 10 is rovided with slde walls 24 and 25 by one 0 which walls each of the signals is supported. In the particular instance as in Fig. 3, the signal unit 22 is supported solely by a screw 26 which passes thru the wall 25 into a lug 27, that is split at 28, and which is threaded, as at 29, leaving the portion 30 unthreaded and havlng a clearance hole for the shank of the screw, so that when the screw is tightened the slot 28 is narrowed.

A ring 31 of the unit 22 has PI0]BCt1 I1g from one side a two-part lug 32 to receive the lug 27 between its members, and a pin 33 passes thru each of the lugs and 1s fixed in the upper lug 32 by a pin 34.

Now, when it is desired'to move the unit 22 in the casinglO, so that the beam of light may be directed to any position with refercure to the axis of the casing, the screw 26 is loosened; this will cause the lug 27 to spring apart, to a greater or less extent, at

the slot 28 and loosen its grip on the pin 33.

When this has been done the unit 22 may be moved laterally, as shown in Fig. 3, by the dotted lines, after which the screw. 26 may be tightened and the beam of light will be defiected laterally from a normal axial position. Now, should it be desirable to elevate or depress the beam of light, the unit*22, or any one of them in the casing 10, may be moved into vertical position shown by dotted lines in Fig. 4, by rotating the unit as a whole upon the axis of the screw 26, whereupon the screw 26 is then tightened and the lug 27 will be held firmly in contact with the casing wall 25 and the lug 27 will firmly grip the pin 33, so that a single screw 26 may be employed for securing either "of the units in an desired position. i-Vhen the unit is defiecte laterally, as shown in Fig. 3, the red unit may produce a field of light 35 unit being located at 37. The next unit in the casing may produce a field 38 along the track, and the third unit may oe adjusted to produce a field 39 so that in this way the red light 35 will be seen first by a train approaching and moving in the direction of the arrow 40, thereupon the yellow signal, having a field 38, will appear, which in most instances is the caution signal, and after the trainmoves further along toward the source of light where the signal is located at 37 the field 39 will appear, which is the clearance signal. In this way the combination of lights may be made to extend a long distance around the curve so as to add considerablpy to the efliciency of the signal, as a whole.

igs. 3 and 4 show specifically a means for adjusting the lamp and lenses within the casing.

Fig. 5 shows diagrammatically a beam 35' of light having its rays in parallel lines projected along a straight piece of track 36'.

The lamp adjusting device, as shown, comprises a rotatable shaft 42 to which is fixed an eccentric 43 in the sup orting ring 51. To the other end of the s aft is fixed an eccentric inside of the socket 48 which socket is also a fixed art of the frame. A bracket 70 is fixed to t e sleeve which is rotatable on the shaft 42 by the screw driver slot 47. The two eccentrics act as one and move the shaft with the sleeve and attached parts .around a central axis so that any desired position for the lamps with respect .to the axis of the lens 7 2 may be secured.

While I have herein shown a single embodiment of my invention for the purpose of clear disclosure it will be manifest that changes may be made in the arrangement and configuration of the parts within the scope of the appended claims.

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

1. A signal device comprising a fixed casing having a. light opemng;. a light signal unit therein; a lug projecting from the unit; a clamping lug hinged to the aforesaid lug, permitting the unit to be adjusted rotatably in a horizontal plane and a screw extending thru a side wall of the casing into the clamping lug to clamp the lugs together and to. immovably secure them to the casing and permitting rotary adjustment in a vertical plane when released by the screw.

2. A signal device comprising a fixed casing havin a light opening; a light signal unit therein; a two member lug rojecting from the unit near the front end thereof; a clamping lug having a perforation and a slot extending therefrom to one end thereof; a pintle pin passing thru the lug members and fixed to the lug on the unit; a screw passing thru a side wall of the casing and thru the slotted end 'of the clamping lug to clamp the lugs together and to fix them to the casing.

In testimony whereof I hereunto subscribed my name.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4636036 *Sep 17, 1981Jan 13, 1987Sasib S.P.A.Multi-color traffic signal
US5433166 *May 12, 1994Jul 18, 1995General Railway Signal CorporationRailway light signal
U.S. Classification362/273, 246/483, 362/231, 246/473.3
International ClassificationB61L5/18, B61L5/00
Cooperative ClassificationB61L5/1836
European ClassificationB61L5/18A3