US2319137A - Automatic railroad crossing signal - Google Patents

Description

0. KITCHEN AUTOMATIC RAILROAD CROSSING SIGNAL May 11, 1943.

2 Sheets-Sheet 1 Filed June 12, 1940 I Il3 INVENTOR. OTIS KITCHEN.

ATTORNEY.

Patented May 11, 1943 UNITED STATES PATENT OFFICE.

1 Claim.

This invention relates to safety devices for railroad crossings and more particularly to improved crossing safety signals actuable by approaching trains for positioning in the path of vehicle travel along intersecting roads.

It contemplates more especially the provision of improved railroad crossing signal devices that serve as a partial obstruction to normal vehicular travel along roads intersecting with railroads to enforce a stop without completely obstructing emergency passage. 7

Numerous signal devices have heretofore been proposed to indicate approaching trains to drivers of vehicles travelling along an intersecting roadway. For the 'most part, known signals either embody indicators that have no obstructing effect on vehicular travel or completely obstruct the railways so that vehicular passage is rendered hazardous or impossible in the event the signals should become inoperative or the driver of the approaching vehicle does not have sufficient time to clear the signal owing to his position of approach at the time of signal operation.

With the teachings of the present invention, it is proposed to combine the advantageous features' of both non-obstructing and complete-obstructing railway signals and crossing gates. To this end', signal means have been provided which respond to approaching trains to occupy a position in the roadway that substantially obstructs passage of vehicles on both sides of the road unless extreme careis exercised to eiiect clearance therewith in the event the signal operating mechanism should become inoperative or the driver of an approaching vehicle is so close to the signal 'at the time it moves to an operative position that avoidance thereof as well as the approaching trains becomes essential. This is important at remote crossings where attendants are not justified and still there is a marked requirement for an effective signal which will prevent collisions between trains and vehicles travelling along intersecting paths.

In such situations, automatic gates and crossing barriers are not entirely satisfactory in that oncoming vehicles may be too close to avoid stopping in frontof the gates or other obstruction and yet have sufiicient clearance to avoid collision with the approaching train had there been an eifective signal alarm serving to inform the approaching motorists. too, ordinary non-obstructing signals are not satisfactory in that drivers of vehicles are not always responsive across'the rails with the thought that a collision thereto in view of apparent clearance for travel can be avoided. Consequently, the known cross-1 ing signals of the non-obstructing and completeobstructing types are not entirely effective unless there is an attendant at the crossing.

One object of the present invention is to simplify the construction and improve the operation and yet afford avoidance with the approaching train.

Still another object is to provide an improved automatic railway crossing signal that is partially obstructing to vehicular travel responsive to approaching trains and yet permits passage therearound by exercising due care when the signal mechanism should become inoperative or the approaching vehicle is so close as to preclude a stop and yet afford avoidance with the approaching train. Y

A further object is to provide a railway crossing signal mechanism that rises intothe intersecting roadway to obstruct the center lane thereof and permit vehicle clearance therearound with the exercise of due care.

A still further object is to provide a railway crossing signal mechanism of a partially obstructing type that automatically rises into the tersecting roadway to obstruct the center lane thereof and permit vehicle clearance therearound. with the exercise of due care.

Still a further object is to provide an improved and simplified railway crossing signal responsive to approaching trains that partially obstructs a vehicle travelling roadway and provides an indicator to the approaching train as to the operation or inoperation of the roadway signal after the crossing has been traversed.

Other objects and advantages will appear from the following description of an illustrative embodiment of the present invention.

Figure 1 is a diagrammatic plan view of an intersecting railway crossing showing signal means embodying features of the present invention.

Figure 2 is a schematic View of a wiring diagram for a railway crossing signal system emboclying features of the present invention.

Figure 3 is a fragmentary sectional view taken substantially along line III-III of Figure 1, parts thereof being shown in dotted outline in advanced position of operation.

Figure 4 is a fragmentary elevational view taken substantially along line IVIV of Figure 1, parts thereof being shown in dotted outline in advanced position of operation.

Figure 5 is a sectional view in elevation of an actuating mechanism with the signal shown concealed in their tunnel compartments taken substantially along line V--V of Figure 1.

Figure 6 is a fragmentary sectional view taken substantially along line VIW of Figure 5.

Figure '7 is a fragmentary sectional view of a gate illuminator control switch taken substantially along line VII-VII of Figure 6.

Figure 8 is a fragmentary sectional view taken substantially along line VIII-VIII of Figure 1.

Figure 9 is a fragmentary plan view of gate cover hinge viewed substantially from line IX-IX of Figure 5.

Figure 10 is a fragmentary sectional view of a hinge taken substantially along line XX of Figure 9.

The structure selected for illustration embodies the customary double railway tracks I9 and ii which intersect with a highway, street or grade crossing l2 along which vehicles such as automobiles l3 and 14 travel in opposite lanes intersecting with the railway tracks ltl I. In the present embodiment, signal arches l5 and 16, in this instance two,.are disposed within the roadway l2, these being of sufficient width to transversely occupy a space that will preclude the double lane travel of vehicles I3 or M in the same direction and partially obstruct single lane travel of the vehicles I3-I4 unless extreme care is utilized in passing to one side or the other of the signal arches l5-l5 depending upon the direction of the oppositely travelling vehicles l3-l4.

It should be observed that the signal arches l5--I'6 are substantially the width of a standard vehicle 13 or H! so as to occupy the center lane of a three-lane roadway l2 while on four-lane roadways the signal arches I5H5 preferably though not essentially should be of double width to permit only a single restricted lane of travel in both directions for reasons which will appear 1 more fully hereinafter. It will be observed, therefore, that the transverse extent or space occupied by the signal arches l5l6 will depend largely upon the width of the roadway 52 or otherwise as commercial practice may dictate to procure the most effective signal results.

In addition to the signal arches li-lii, auxiliary illuminator signals l'l-lil are erected on both sides of the roadway I2 proximate to the track I!) so that preferably red light rays l3 and 20, respectively, will emanate therefrom toward the approaching vehicle l3. A similar pair of auxiliary illuminator signals 2i and 22 are erected on both sides of the roadway l2 proximate to the track ll so that preferably red light rays 23 and 24, respectively, will emanate therefrom toward the approaching vehicle l4. It should be noted that the illuminator signals i'l8 and 23-22 may be of an audible type or an audible signal may be combined with the illuminating signals ll-IB depending upon the requirements or dietates of commercial practice.

An additional set of illuminator signals 25 and 26 each comprising, in this instance, a set of two lights 2l28 and 2il38, respectively, are mounted adjacent the side of the tracks ill i, respectively, at an appreciable distance from the roadway l2to emanate light in the direction of train travel so that the attendants can determine therefrom whether or not the signal arches I 5l 6 together with the illuminated signals l'll8 and 2 l 22 are in proper operation as the train travels beyond the roadway i2.

From these illuminator signals El-23 and 2933 which are each preferably though not essentially green and red, respectively, the attendants on the trains passing beyond the roadway l2, can determine whether or not the signals Iii-4B, ll|3, and 2i22 have operated properly and returned to their initial position or" inoperation so that a report can be made at the next train stop as to the operation of the signals along the entire railway system. The operation of these various signals are entirely automatic and will appear more fully from a description of the circuit.

In order to accommodate the signal arches !5l ii as well as the actuating mechanism therefor, an elongated pit 3| is preferably excavated longitudinally along the roadway l2 and across the tracks iii-H to provide substantially rectangular chambers 32 and 33 which communicate through passages 35 and 36 to a chamber 31 (Figure 5) that serves as a power source for actuating both signal arches l5-I5. The elongated cavity SI with their chambers 32-3331 and their communicating passages 3%i35 are preferably lined with waterproof walls of any suitable material such as concrete to maintain them relatively water-tight in conjunction with the roadway top surface 38 constructed from similar material.

To this end, the signal arch receiving chambers 3233 of identical construction are each provided with confronting cover plates 39 and 40 that terminate in a plurality of hinge loops 4| (Figure 9) that are spaced to receive complemental hinge loops 42 (Figures 9 and 10) comprising an integral part of a substantially rectangular opening liner 43 which is anchored to and occupies an opening 44 provided in the roadway crossing surface 38 above the cavities 32 and 33 (Figure 5). Hinge pintles 45 and 45 extend through the aligned hinge loops 4 1-42 that pivotally connect the closure plates 39- 30 to permit them to swing upwardly to permit the elevation of the signal arches l5l6 from the chambers 32-33.

In order to render the closure plates 39-40 substantially water-tight and to effectively close the openings 44 above the signal arch chambers 32-33, a steel plate 41 is welded proximate to the edge of the closure plate 39 (Figure 4) to overlap the top surface thereof and contact the edge regional surface of the confronting closure plate 46. It should be noted that the closure plates 3940 are somewhat spaced from each other to present a clearance space 48 that is covered by the plate 47 that also overlaps an elongated slot 50 provided in the adjacent surface proximate to the end edge of the other clo sure plate 43 to preclude the entrance of foreign substances and provide a drain along the slot 59 which will avoid any deposits in any event on the signal arches lE-lfi. End plates 39'-40 are attached to the side edges of closure plates 394ll. The plate 39' has a rounded edge 39" and plate 40 has a square end 69 which is overlapped by the rounded end 39", thereby permitting the smooth opening of both closure plates 39-43. The side covers 39:l0' tend to prevent dust, snow or rain from blowing into pit through the ends of the closure plates 394El when in their fully open position.

So that closure plates 39-40 will be closed in response to their own weight as well as by the urge of springs, coil springs envelop the hinge pintles -46 between the hinge loops 4| to exert a closingurge'on the closure plates 394|l auxilia'ry to the gravity urge thereon. To preclude the pintles 45-46 from axial displacement from the hinge loops 4|42, threaded studs 52 (Figure 4) extend through one of the hing loops 42 proximate to the end of the doors to engage the pintles 4546 and preclude their rotative axial displacement. Suitable hinge cover plates 53 and 54 are welded or otherwise secured to the closure plates 39-4i! to extend over the integrally associated hinge plates 4| to provide an overlapping protective cover precluding the access of foreign substances and water therethrough.

To this end, the hinge cover plates 53-54 terminate in arcuate extensions 53'54' to enter correspondingly shaped arcuate recesses 55and 56 formed in the adjacent region of the roadway surface 33 to accommodatethe hinge cover plates 54 when the closure plates 394|l have been opened responsive to elevating the signal arches |5l6- as Will appear more fully hereinafter. It should be noted that proper water drains are provided in the chambers 323331 to eliminate any moisture or water that may collect therein.

In order to enable access to the instrumentalities confined in the central chamber 31 of the pit 3|, an opening or man-hole 51 is formedof sufllcient size in the road surface 38 to permit an attendant to pass therethrough for access for. repair, replacement or other purposes incident to the maintenance thereof. A metallic man-hole cover 58 rests upon shoulders 59 formed along the pheriphery of the man-hole 51 to serve as a support for the cover 58 that has its top surface in alignment with the surface of the roadway |238. It will be apparentQtherefore, that the pit 3| will be effectively protected against the entrance of moisture, precipitation, or foreign substances that would impairthe operation of operating instrumentalities to be hereinafter de-' scribed. 1

The signal arches i6 comprise substantially rectangular metallic angle iron frames 60 which terminate upwardly in a pointed top member 6| extending thereacross, the top member 6| preferably being of triangular cross-section to cooperate with confronting rollers 62 and 63 journalled in brackets 64 and .65, respectively. The roller brackets 64--65 are attached to the underside of the closure plates 394fl proximate to their confronting edges for positioning in the path of th signal arches l6 so that the converging surface of the top member 5| is-disposed in the path thereof to elevate the closure plates 39-40. v p

It should be noted that the .top linear edge 66 of the triangular top member BI is in alignment with the clearance space 48 to normally extend between the closure plates 39-46 so that actual contact therewith is precludedby virtue of the wedging action on the closure plate rollers 52-| 53 that traverses the converging sides of the top member 6| and continues to contact the edges of the signal frame 60 as the signal arches l5- l6 are elevated responsive to instrumentalities to be hereinafter described (Figure 4).

This will serve to automatically open the closure plates 3940 that normally close the signal arch confining chambers 32-33. As the signal arches |5-|6 recede for confinement within the chambers 3233, the closure plates 39-40will touch each other responsive to the urge of gravthe circuit to the illuminators 16.

ported in spaced'relation to the ends of the central arch chambers 33 by means of a plurality of brackets 13, in this instance three, mounted along each end wall thereof for attachment thereto by means of suitable fasteners 14. A suitable figure such as a facsimile of a policeman 15 is preferably attached to the back plate 61 of the signal arch frame 60 to serve as a stop indicator illuminated by one or more lights 16,

' in this instance three, fixed to the underside of the top edge of the signal arch frame 60 (Figure 3).

These lights become energized as the signal arches |5|6 are elevated into operative position to serve as a partial obstruction in the roadway 12 when displaced from its initial inoperative position of confinement within the two chambers 32--33 as will appear more fully hereinafter. So that the illuminating lights 16 will become energized responsive to the elevation of the signal arches |5-|6, the frames 60 thereof are provided with an insulator block 11 fixed to th side flange 68 of the back plate 61 (Figure 7) to mount an elongated conductor plate 18 thereon.

A terminal 19 carries a contact in the path of the conductor plate 18 so as to effect contact therewith as the signal arches |5-|6 are partially elevated and continue in their vertically upward dis-placement to their maximum operative position above the surface of the roadway i2. As the signal arches 5|6 recede into their respective pit chambers 32--33, the switch terminal contact 80 rides off of the conductor 18 to break Suitable lead wires 8| and 82 extend from the conductor plate 18 and switch terminal 19, respectively, to a source of energy (not shown) so that the illuminator 16 will be automatically responsive to the position of the signal arches |5Ii3.

The signal arches |5-|6 are elevated and lowered by means of links 83 that are pivoted as at 84 to the back plate 61 along a vertical median line thereof. The links 83 terminate in an apertureol boss 85 that confronts a similar boss 85 formed on a crank arm 81 to receivean interconnecting pintle 88 therethrough. The crank arnr81 is fixed to a shaft which rotates with a spur'gear 89, the mounting shaft thereof being journalled in a bearing bracket 98 that has a depending standard 9| resting upon the floor 82 of the signal arch chambers 323-3.

The spur gear 89 meshes with a pinion 93 that is carried by a shaft 94 terminating in a coupler 95 which is operatively connected to double armature shafts 96 of an electric motor 9?. The electric motor 91 is mounted on a pedestal 98 fixed to the floor 98$ of the central pit chamber 31. The shafts 9496 are journalled in bearing brackets Hi0 and IBI fixed to the floor m2 of the communicating pit passages 35-36 for journalled support of the shafts Qt-Qfi in horizontally spaced relation therewith. It will be observed, therefore, that with the rotation of the motor 91, the signal arches |5 |6 will be elevated to their operative position and 'then returned to their inoperative position-fortotal confinement in the pit chambers 32--33 responsive to controls that will be more particularly described hereinafter in connection with the schematic wiring diagram.

,In order to control the operation of'the motor 91 so that the signal arches I5-- I6 will be elevated and lowered to their extreme positions and the motor 91 rendered inoperative in consequence thereof, limit switches I93 and I04 are supported in the signal arch chambers 32--33 by means of brackets I05-I06, respectively. The brackets I85-Il!6 are anchored to the wall of the pit chambers 32-43 to present upper and lower resilient limitswitch contacts I01 and IE8 in the path of a trip I09 fixe'cl to the side wall of the signal arch frame 60.

The resilient limit switch contacts Ifl'I'-l'l)8 together with the trip I09 are in the circuit with the electric motor 91 to efiect the energization and de-energization thereof for operation of, the signal arches I5I6 automatically responsive to the approach of trains travelling on tracks H3 and I I. It will be observed that the tracks IE! and I I are each provided with insulated track sections I I-I I I on both sides of the roadway I2 on track It and on both sides of the roadway I2 on track I I, respectively, at predetermined positions of approach at any suitable distance from the roadway I2 depending upon the speed of travel of the train and the timing of the signal arches I--l6.

Similarly, insulated sections H2 and H3 are provided on both sides of the roadway I2 on the track II at a corresponding distance on the opposite side of the roadway I2 to control the operation of the electric motor 91 together with the auxiliary light signals I'II8 and 2I-22 as well as the green-red sets of signals 21-28 and 2930 positioned for observance so that the attendants on the trains passing beyond the roadway I2, can determine whether or not the signals I5I6, I I--I 8 and 2 I-22 have operated properly and return to their initial position of inoperation. The insulated track sections IIOI II and II2-I I3 in tracks Iil-I I, respectively, will control the operation of the electric motor 91 and the signal arches I5-I5 responsive to trains approaching in the direction of the arrow on track It and in the opposite direction indicated by the arrow on track II.

The control circuit schematically shown in Figure 2 is arranged so that a train passing on insulated track sections IIIl on track II] will have its wheels bridge across these rails and close the low potential signal circuit to energize a coil I I4 comprising a locking relay. The looking relay IM closes switch contacts Il5l I6 to energize the signals comprising red lights and/or bells I'I-I8 and 2I22 together with the operating indicator red-green lights 29-30. As the train passes on to the next rail section III, a coil H8 of a contactor switch is energized to close switch contacts II9-'I2Il. This starts the electric motor 91 which elevates the signal arches I5-IG on both sides of the tracks IIII I.

It should be noted that as the signal arches I 5-I6 start to rise, the signal arch trip Hi9 rides ofi of the spring terminal I88 to close the lower limit switch I04. As the signal arches I5I6 reach their maximum upward position of displacement, the signal arch trip I09 engages the spring contact Ifl'I to open the upper limit switch I03. This deenergizes andstops the Cit motor 91. As the train proceeds beyond the crossing and passes off the insulated section I I1 and onto track section III, the coil is deenergized and contacts II9-I2Il open while simultaneously closing contacts II9I2I of this double acting relay switch II8. This again starts the motor 91 to lower the signal arches I5--I6 until the signal arch trip I09 engages the lower limit switch contact I08 and opens the lower limit switches I64 to deenergize the motor 91.

As the train crosses beyond track section II I, an unlocking relay coil I22 is energized to unlock the switch contacts I I5I23 and allow con tacts I I5I It to open and close contacts II5-I24. This turns oil the crossing lights I'IIB and 2I-22 while turning on the green train attendant indicator lights 21 and 29. This evidences that the cycle of operations has been completed to the attendants on the passing train. It should be noted that the attendant indicator lights 2'I28 and 293I) may be controlled directly responsive to the operation of the signal arches I5I6 or the electric motor 91 in much the same Way as the auxiliary signal lights III8 and 2I--22. The light circuit lines (Fig. ure 2) are the signal circuit which preferably carry a potential of 6 to 12 volts A. C. or D. C. while the heavy lines are the power circuit and preferably carry a potential of volts A. C. or D. C. or any other suitable voltage.

The cycle of operations described in connection with the approaching trains travelling in the direction indicated by the arrow on track I0 is identical with the cycle of operations initiated by a train or trains traveling in the direction of the arrow on track II in that its track sections II2, I25, II3 are connected in parallel with track sections H0, 1, III of track III.

With the arrangement of parts above described, the signal arches I5I6 comprise a fractional part of the roadway I2 so that they will obstruct all travel of vehicles I3I4 on all lanes thereof except single outside edge lane. Consequently, when the signal arches I5-I6 are elevated to their maximum upward limit, they will partially obstruct the roadway I2 and serve as a substantial indicator causing all vehicular travel to be observant thereof and. exercising care to avoid collision therewith. This effectively serves to stop all motorists and respond to the signals I5I6, I'II8 and 2I22.

With the allowance of single outside edge lanes, however, the vehicles I3I4 can still cross over the tracks IU-II in the event the signal arches I5I6 should remain inoperative in their extreme upward position or should vehicles I3-I4 be over any part of the signals I5--I6 at the time they start to operate responsive to approaching trains and tracks IIJ and/or II. If the signal arches I5I6 were extended for the full width of the roadway I2, there would be situations wherein motorists would find themselves unable to avoid collision with the usual gates that obstruct the full width of the roadways IZ. This would be equally hazardous with the usual light and bell signals that merely indicate an approaching train without serving as as an obstruction to the path of vehicular travel. Under such circumstances, the drivers of the vehicles I3I4 are inclined to beat the train to the crossing and as a result such signals have not served any real efiective purpose.

Various changes may be made in the embodiment of the invention herewith specifically dedinal median line of said roadway, said signal members characterized by a dimensional width that conforms to a fractional part of the roadway width to obstruct alllanes of vehicle travel except single outside edge lanes conforming substantially to the standard width of a vehicle, and hinged closure plates over the top opening of said pit, rollers depending from said hinged closure plates in the path of said rigid signal members to effect contact therewith for operation responsive to the vertical displacement of said rigid signal members.

OTIS KITCHEN.

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