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Publication numberUS1531987 A
Publication typeGrant
Publication dateMar 31, 1925
Filing dateOct 12, 1922
Priority dateOct 12, 1922
Publication numberUS 1531987 A, US 1531987A, US-A-1531987, US1531987 A, US1531987A
InventorsSmith Dallas H
Original AssigneeSmith Dallas H
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Grade-crossing control
US 1531987 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)


.GRADE CROSSING CONTROL s Smets-sheen 1 Filed Ot. 12 1 1922 March 3L 1925- D. H. SMITH `G'UDE CROSSING BONTRCL Filed octw @12 g 192; shee-tssneet March 3L W25,

D. H. SMETH GRADE CROSSING CONTROL 3 ASheserts-Sheet 3 Filed Oct. 12 1.922


fr @EWS Patented Mar. 31, 1925.




Application led October 12, 1922.l Serial No. 593,949.

To all whomz't may con-cem:v

Be it known that-I, DALLAS H. SMITH, a citizen ofthe United States, residing at Maricopa, in the county of Pinal and State ofAriz ona,:ha-ve invented new and useful Improvements in Grade-.Crossing Controls, of whichthe following is a specification.v

This-invention relates to'grade crossing controls and has .for its object to` vprovide automatically operative barriers for retarding or preventing the running of a road vehicle` onto .and across a railroad track at grade crossings.

Another object of the inventionis to provide grade crossing barriers vwhich are controlled, preferably electrically, by the entry of a rolling stock of railroad systems into a zone extending a suitable distance in either direction from the line of the highway or road crossing.

Another object o f theinvention is to proi vide barrier means .rendered effective tore# tard the advance'of a vehicle coming toward" the railroad tracks and yet operative to'per- 5 mit the-passage of a vehicle over the barriers* when leaving the railroad tracks. 1

. Anotherobject' is jto'prov'ide a'barrier actuating means including radjacent devices one operative yieldingly by the passage of a road Vehicle to set barriers ybetween the vehicle and the railroad tracks in its path, and the other de vicebing effective as al barrier to prevent by-passing of' the operating means. 4

Another object of the invention is to`provide a barrier adapted to be automatically set by rolling stock of a railroad system ap.- proaching a crossing.

mani-fest in the following specification of embodiments of the invention illustrated in the accompanying drawings, wherein-f Figure 1 is a diagrammatic longitudinal elevation and section of the crossing control i in the normal position.- v.

Fig. 2 is a similarview showingtheactw ating platform of the system tripped byvan automobile and the s uccessivebarriers set i and as being automatically locked by a contiguous train on a railroad track.' 'v

Fig. 3 is a transverse section -and partial elevation showing the actuating platform and a contiguous yielding preventer.

Other objects and advantages will be made Fig.l 4 is a sectional view transversely of .the apparatus showing the yieldably mounted barrier.

Fig. 5v is a longitudinal Asection Voa form of the apparatus which is Vwholly train controlled.

' Fig. 6 is a transverse section on line 6-46 of Fig. 5.

' Figs. 7 to 9 illustrate a. slightly modified form of the invention.

The invention is Shownas including a platform 2 which-is pivoted as at 3 upon suitable mountings disposed in a roadway at a considerable distance from the tracks T of a railroad system, the proximity of which it is desired to give notice, effectively, to the driver of highway vehicles, more particularly motorv vehicles, such as automobilists and drivers of other motorvehicles; van automobile A being here indicated.

The platform y2vis rigidly connected to a lever device 4 and this in turn is connected as by a link 5 to an elongated connecting orpush rod 6 which, for convenience, -rotection and ease of operation, may be s idably mounted in a tubular guide or. pipe 7. This pipe is shown as sunken below the roadway and communicates with severali pits 8, 9 and 10 into and through which the push rod 6 extends. In the pit 9 is a link device 6 which .is connected to the push rod 6 and also 'to a hingdly mounted primary barrier 1'1 which may be in the formof a transversely extendving abutment of any suitable design. This abutment isv adapted to be thrown to an up' -crossing.` On the'rock shaft 15 there is p-ivoted asecond barrier or abutment 16 having a plane top 17 which latter is desi ed to be'lowered into the plane of the'higvliay as shown in Fig. l.

The abutments 11 and 16 are preferably yieldingly connected so as to tilt on their rock shafts when engaged by a vehicle passing from the railroad tracks T toward and over the planes of the abutments while they may be in the projected effective position as to vehicles approaching the railroad tracks. is

Yielding connection may be provided in various ways, and as here shown around -the rock -shaft 15 there is arranged a helical spring 18 secured at 19 to the shaft. The

f opposite end of the spring bears against the tracks and for controlling the release of the barriers. The push rod 6 is normally thrust in a direction to retract the barriers from an exposed position and bring their planes 12 and 17 to the road level position as by means of an expansion spring 20, though other suitable device may be used. Therefore, the function of the spring 2O is to restore the barriers to concealed position as soon as the vchicle'A passes'off of the actuating platform 2. p

The retraction of the barriers is train controlled as by means of a check device consisting here of a pneumatic mechanism including a cylinder 21 disposed in the pit 10 and which operates a piston 22 connected by ink 23 to the lever arm 14 of the rock sha 15. The cylinder 21 is provided with an air inlet port 21 so that as the spring 20 reacts to retract the abutments the piston 22 may slide freely in its cylinder 21. However, should a train be within the given zone` along the railroad tracks T it is then desirable to prevent the retraction of the barriers. To that end means, here shown as electrical, are employed to control the pneumatic cheek device.

The electrical control means includes a source of current as a battery 25 anda magnet 26 in lcircuit lwith the battery; the circuit including wires 27 attached to the railroad tracks T and the circuit is closed" from track to track by the metallic elements of rolling stock when engaging the electrically connected tracks within .the danger zone. y A

As a train, for instance, closes the electrical circuit the magnet 26 is energized and actuates an armature 28 which has its upper end constructed and arranged to serve as a valve to close the air-inlet port 21 of the pneumatic cylinder 21. Therefore,uponj/ the approach .of the train or other element'-l of rolling stock at the grade, the v alve device 28 is closed and if a vehicle A operates the platform 2, the latter sets Jthe barriers 11 and 16 and though the ,vehicle may pass from the operating platform the automaticl restoration of the barriers, as by the springs 20, is prevented since the movement of 'the piston is so retarded in the closed cylinder 21 that the barriers will be held effective to retard or prevent the passage of the vehicle A toward the tracks.l

As the railroad train clears the danger zone, the circuit'of the -magnet 26 isibrokcn and the valve device 28 is released and antomatically opened as by a spring 29 and this permits the automatic retraction of the abutments.

lt is desirable that the control platform 2, Fig. 3, does not extend entirely acrossI the highway but only across one side thereof thus leaving the opposite side for the passage of vehicles in a reverse direction. But it is desirable to provide means for preventing reckless vehicle drivers from passing around the operating platform 2. so as to avoid the operation and setting of the barriers. Such avoidance of the operating platform may be 'effectively secured by the arrangement of a preventer which may con'- sist of a guard 30 which maybe pivotally mounted on the rock shaft 3 and yieldingly held in elevated position as by a spring 3l. The preventer 30 is shown in Fig. 1 as disposed toprojectobliquely in a direction toward vehicles moving along the highway toward the tracks T, While the operating platform 2 is shown, in Fig. 1, as inclining upwardly and forwardly in the path toward the tracks. Therefore, the reverse inclina- ,tion of the preventer 30 serves as means for stopping vehicles approaching the tracks but provides for the depression of the pre venter downwardly toward the roadway by vehicles moving away from the tracks.

A somewhat modified form of the invention is shown in Figs. 5' and G in which the barrier is wholly under the cont-rol, in its setting operation, of the railroad rolling stock and means are shown for projecting the barrier to effective position when a train enters the danger zone along tracks T at a grade crossing. 1

- The abutment setting mechanism includes a quadrant 35 which may form a part of the abutment and is secured to a rock shaft 3'? to which is attached a lever arm 38. This lever arm is connected by a link. 39 to a segmental gear 40 journaled in a bearing and engaging a pinion 42 secured to the shaft of a reduction gear 4B which may conlil) As the train leaves the tracks of the.

sist of a sprocket Wheel engaging a4 sprocket to a vbrush 53 secured lto the shaft 40 of the segment 40." 'This brush is in electrical engage-ment with a contact 'plate 54 from ywhich extends awire 55 feeding-the motor i 46.

the companion terminals 50 and -51 but is lautomatically lclosed by a cross contact ,56

having a wireconnection 59 to a source of The motor circuit is normally broken at secured to an armature 57 of a .solenoid 58 currentas a battery 60. From the battery extends a Wirel connected of the u tracks -'I,and from the :other track extends a return circuit wire 62 leading 4to thevsolenoid. Thus, rolling stock passing into the danger-Zone willi'close the .solenoid circuit and the .cross contact membery -56 will be actuated and the motor circuit closed at vthe contacts '50 and A'51. Thereupon, the motor Will be energized and the trairrof` gears connected thereto will throw .theabutment 35 to the projected position.- i 'It is desired to latch the abutment y1n effective position positively While the train is passing .the vcrossing'zone and yet it is desirable to cut out the motor circuit as soon as the barrier has been set'.

For this ,purpose the quadrant '36 of the barrier is designed to be locked by a latch which is shown as connected to the armature66 of a solenoid "67 from which runs a Wire 68to a contact plate 69 positioned contiguous tothe contact plate 54. These plates are so designedthat AWhile the contact brush 53 is initially traversing a portion f the plate54, themotorcircuit is closed,.and during" a further movement of the brush 53, itv will concurrently engage contiguous portionsof the plates 54`and 69, and during this l moment While ther motor is. still running on l closed circuit, the solenoid 67 will be energized and the latch`65 thrown into'locking engagement With the toothed quadrant 36.

As vthe brush 53 of the motor circuit moves ofi' of its contact plate `54, the circuit is broken but momentum of the motor carries the brush 53 onto the solenoid circuit which includes a wire 67 connected to the generator 'circuit Which still remains closed and danger zone, the circuit of the solenoid 58 is broken and the contact member 56, is thus released and breaks 'circuit at contacts 50 Vgenerator circuit.

and 51. Thisv deenergizes the solenoid 67, which as above stated, is connected to the lVhen released the barrier 35 will gravitate to its retracted position to be outof the way of traliic.

It may be desirable'to prevent lbarriers- 11 and 16 from being set When the platform 2 is depressed by a road vehicle when there is no train in the danger zone at the grade crossing. Thus',in the absence of a train, the road vehicle passing over the platform could run without hindrance of the barriers toward the railroad tracks. But in the contingency that a train is inthe danger zone, it-is thendesirable toprovidefor the setting of the barriers, and this mode of operation is obtained by l.mechanism shown in Figs. 7, 8 and 9 which is substantially similar to the mechanism of Figs. 1 and 2'.

- To provide for the depression of a platform 2,Y Fig. 7, Without operation of the barrierl push rod'6, this latter is shown as beingbroken or of .sectional form, the initial section 6l 'being' provided with a shoulder`6b and is connected by the link 5 to the platform'r 2.1 The main rod section 6 isfadapted to be connected or coupled to the initial section 6a to be operated .thereby 'only in the event that there is a train in the danger Zone at thecrossing, and means are provided for automatically controlling the coupling of the push rod sections.' This means includes electrical apparatus involving preferably a normally-'closed circuit 70 including a ymagnet 71 normally Yholding Aopen av circuit switch 72 in-the 'circuit ofthe battery 2 5 and `which circuit in- A cludes` the magnet 26- controlling the pneumatic check valve 28., kThesvtitch 72 is connected by a line 73,'1Qg1dingfto a magnet 74 which. is shown v'as "arranged in, 4a pit through Which the. push rod passes and in which pit there is provided a latchA 75 here shown as Connected tothe end of the push rod6 which is contiguous to the shoulder 6b. Thelatch 75 is provided with an armature 76 attractive by theA magnet 74 when the circuit of the battery 25 is closed by the switch 72. The switch 72 which, as above stated 'is normally opened by the closed circuit 70,

will-be released by the entry of a train on the tracks T, Fig. 7, which train will cause `the shortening of the circuit ofthe magnet 71 which circuit includes a battery`70a from which runs the short `Jcircuit line 70". The circuit 70 is shown Aas connected to one of thetracks T andthe short circuit Wire 70b to the other track, and therefore the rolling stock on the tracks will short the circuit of the battery 70n andthe magnet 71 will be deenergized. This Will permit the closing of the switch 72 as by itsspring 72a, Whereupon the latch 7 5 will be drawn to the effective position in front of the" shoulder 6b on the initial rod section 6. Therefore, vat this arrangement of the parts, if a vehicle depresses the platform 2, then the rod 6 beis in closing relation-to the pneumatic check i cylinder 21. From the above it will beseen, therefore, that the platform 2 `may be depressedl and will actuate the rod section 6a without shifting the main rod 6, and a vehicle may` then pass without obstruction over the crossing. -V

The platform is shown in Fig. '7 asbeing restored to uppermost positionby a spring 8O connected to a piston rod 8l which in turn is connected to the link 5. The piston rod 81 has apiston 82 operating in a dash pot- 83 which will permit the rapid downward movement of the platform 2, but will check the action of the springSO in restoring the platform to elevated position for the purpose of preventing the platform from rising too quickly and engaging the rear wheels of the actuating road vehicle, the front wheels of which trip down the platform l Further embodiments, modifications and changes may be resorted to within the spirit of the invention as here claimed.

What I claim is:

l. In combination with railway tracks at a grade crossing, road vehicle operated barrier means adapted to be exposed across a road or highway approaching the railway tracks to impede vehicle traffic on the highway, and means under control of railway rolling stock for controlling the operation of the barrier means. v

2. In combination with railway tracks'at a grade crossing, road vehicle operated barrierV means sunk in and adapted to be exposed across a road or highway approaching the railway .tracks to impede vehicular trafic on the highway, and electrical means under the control of railway rolling stock for controlling the operation of the barrier means. i

3. In combination with railway tracks` at a grade crossing, road vehicle operated barrier means adapted 4to move from a clear position in a roadway to aibarricading position, means for operating the barrier means to render the same effective, and railway rolling stock controlled means for holding the barrier means in eiiectivev position.

4. In combination with railway tracks at a grade crossing, -road vehicle operated barrier means adapted to move from a clear position in a roadway to a barricading position, means for operating the barrier means to render the same effective, `and railway rolling stock controlled means for holding,v

when the rolling stock clears the danger zone.

5. In combination with railway tracks at a grade crossing, road vehicle operated barrier means adapted to move from a `clear position in a roadway to a barricading positio'n, means for operating the barrier means to renderl the .same effective, and railway rollingstoek controlled means foi holding thebarrier ineansin effective position, said controlled means including an electrical circuit having connections to the railway tracks and which circuit is closed when the rolling stock engages the electrically connected tracks.

G. In combination with railway tracks at a grade crossing, barrier means adapted to be exposed across a road or highway approaching the railway tracks to impede vehicular traffic on the highway, means under control of railway rolling stock for c .ntrolling the operation of the barrier means, and a road vehicle actuated means for setting the barriers.

7. In combination with railway tracks at agrade crossing, barrier means adapted to be exposed across a road or highway approaching the railway tracks to impede vehicular traffic on the highway, means under control of railway rolling stock for controlling the operation of the barrier means, a road vehicle actuated means for setting the barriers, and means for automatically retracting the barriers when released by the railway controlled means,

8. In combination 'with railway tracks at .a grade crossing, barrier means adapted to be exposed across a road or highway approaching the railway tracks to impede vehicular traiiie on the highway, means under control of railway rolling stock for controlling the operation of the barrier-means, and a road vehicle actuated-moans for setting the barriers, the barriers being yieldable under pressure in one direction to permit the passage of vroad vehicles.

9. In combination with railway tracks at a `grade crossing, barrier means adapted to be, exposed across a road or highway approaching the 'railway tracks to impede ve- Ihiculantraiiic on theliighway, means under `control of railway rolling stock for controlcontrols and adapted to retard advance of a -road vehicle to railway tracks at a grade crossing, barrier means, a vehicle operated platform for actuating the barrier means to render the same effective, and a preventer contiguous to the said platform to prevent lay-passing of vehicles around the platform.

11. In an apparatus for grade crossing controls and adapted to retard advance of a4 road vehicle to railway tracks at a grade crossing, barrier means, a vehicle operated platform for actuating the barrler means to render the same effective, and a preventer 10 contiguous to the said platform to prevent bypassing of vehicles around the platform, the preventer being yieldable to permit the passage of vehicles from one direction.

In testimony whereof I have signed my 15 name to Jthis specification'.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4133140 *Nov 14, 1975Jan 9, 1979Devices Development CorporationSafety mechanism for highway exit ramp
US4134230 *Apr 4, 1977Jan 16, 1979Roy Richard MMotorcycle racing starting gate
US4998843 *Apr 24, 1990Mar 12, 1991Gerard MotheModular anti-intrusion barrier
US6223125 *Jan 6, 2000Apr 24, 2001Brett O. HallCollision avoidance system
US7484905 *Apr 18, 2005Feb 3, 2009Universal Safety Response, Inc.Energy absorbing bollard system
US20060029467 *Aug 5, 2004Feb 9, 2006Johnson Russell IStarting gate for motorcycles and the like
US20060233609 *Apr 18, 2005Oct 19, 2006Gelfand Matthew AEnergy absorbing bollard system
USRE38870 *Jun 26, 2001Nov 8, 2005Brett Osmund HallCollision avoidance system
WO2000046775A1 *Feb 3, 2000Aug 10, 2000Brett HallCollision avoidance system
WO2006113120A2 *Apr 4, 2006Oct 26, 2006Universal Safety Response, Inc.Energy absorbing bollard system
WO2006113120A3 *Apr 4, 2006Apr 16, 2009Universal Safety Response IncEnergy absorbing bollard system
U.S. Classification246/300, 246/128, 49/33, 340/933, 340/928, 116/63.00R, 246/473.1
International ClassificationB61L29/00, B61L29/02
Cooperative ClassificationB61L29/026
European ClassificationB61L29/02A1