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Publication numberUS3167282 A
Publication typeGrant
Publication dateJan 26, 1965
Filing dateFeb 3, 1964
Priority dateFeb 3, 1964
Publication numberUS 3167282 A, US 3167282A, US-A-3167282, US3167282 A, US3167282A
InventorsReigh Clarence J
Original AssigneeFrances I Hursh, Hursh, John R Hursh, Provident Tradesmens Bank And
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Railroad warning device
US 3167282 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

3 Sheets-Sheet l S. R. HURSH ETAL RAILROAD WARNING DEVICE Jan. 26, 1965 Filed Feb. 6, 1964 ATTORNEYS Jan. 26, 1965 s. R. HuRsH ETAL RAILROAD WARNING DEVICE Filed Feb. 3, 1964 5 Sheets-Sheet 2 FIG. 4.

INVENTOR` SAMUEL R. HURSH 8| CLARENCE J. REIGH BY 6% @we ATTORNEYS Jan. 26, 1965 s. R. HuRsH ETAL. 3,167,282

RAILROAD WARNING DEVICE Filed Feb. s, 1964 3 Sheets-Sheet 3 INVENTORS SAMUEL R. HURSH 8: CLARENCE J'. REIGH BY @.Js @WQ ATTORN EYS United States Patent O RAILROAD WARNING DEVICE Samuel R. Harsh, 423 Bryn Mawr Ave., Bala-Cynwyd, Pa., and Clarence J. Reigh, Altoona, Pa.; said Reigh assignor to said Hursn; Frances I. Harsh, John R. Hursh, and Provident Tradesrnens Bank and Trust Company, executors of said Samuel R. Hursh, deceased Filed Feb. 3, 1964, Ser. N 343,184

3 Claims. (Cl. 24d-124) This application is a continuation-in-part of our earlieriiled copending application, Serial No. 788,226, tiled Ianuary 21, 1959, now abandoned, entitled A Railroad Warning Device.

This invention relates to a railroad warning device, and more particularly concerns a railroad warning device for warning a gang of workmen working on a railroad track of the approach of a railroad train.

Conventionally, when workmen are working on or near the tracks of a railway, a watchman is required who is stationed far down the track and is on the lookout for oncoming trains. Upon seeing an approaching train, the watchman sounds a whistle and otherwise gives notice to the workmen to clear the tracks. Two watchmen are required, one for each direction away from the location of the work gang. When the gang is working on a curved portion of the railway, several watchmen are required and are posted at spaced positions around the curves. This use of watchmen or whistle men is not entirely safe since he may fail to see the train due to inattention or whatever.

Additionally, this use of watchmen or whistle men is eX- pensive, with nine hundred to twelve hundred watchrnen being used in a single day on one railroad alone.

It is an object of this invention to provide means for Warning a work gang of the approach of an oncoming train without the use of watchmen or whistle men.

It is another object to provide such warning means which is safe and which operates automatically, and does not depend for operation on the close attention of a watchman or whistle man.

It is another object of this invention to provide such means which is inexpensively constructed and operated.

It is another object of this invention to` provide such means which is so simply operated that it does not need a signal man to install or operate it. On the contrary, it may be installed and operated by an ordinary laborer without special skills.

It is another object of this invention to provide means for warning a work gang of an oncoming train, which means is fail-safe, that is, if the equipment fails, the warning means is actuated, thus sounding the warning.

It is another object of this invention to provide warning means which is portable and easily installed and carried by one man.

It is another object of this invention to provide warning means which does not interfere with the railroad signal circuits.

Other objects and advantages of this invention, including the ease with which it may be adapted to existing equipment, will further become apparent hereinafter and in the drawings, in which:

FIG. l is a diagrammatic View of a railroad warning device constructed in accordance with this invention;

FIG. 2 is a view in top plan of the sensing means which forms an element of the railroad warning device of this invention;

FIG. 3 is a view in side elevation of the sensing means of FIG. 2;

FIG. 4 is a view in front elevation of the sensing means of FIGS. 2 and 3;

FIG.' 5 is a view in section taken as indicated by the lines and arrows V-V which appear in FIG. 4;

FIG. 6 is a diagrammatic view of the electrical control circuit which forms an element of this invention;

FIG. 7 is a diagrammatic View of one of the alarm means which may be used with this invention;

FIG. 8 is a diagrammatic view of another alarm means which forms an element of this invention; and

FIG. 9 is a view in section along the line IX--IX of FIG. 5.

Although speciiic terms are used in the following description for clarity, these terms are intended to refer only to the structure shown in the drawings and are not intended to define or limit the scope of the invention.

Turning now to the specific embodiment of the invention selected for illustration in the drawings, there is shown a railroad warning device for warning a gang of workmen workinfy on a railroad track of the approach of a railroad train, which railroad warning device includes a sensing mechanism having a rail depression detector 11, represented in FIG. 1 by the arrow and shown in detail in FIGS. 2-5, a radio transmitter 12 with its control circuit 13 (FIG. 6), an alarm mechanism 14 with its tuned radio receiver 15 (FIG. 8), and another alarm mechanism 16 with its tuned radio receiver 17 (FIG. 7).

Alarm mechanism 14 is positioned at location 18 (indicated by dot-dash lines) where the gang of workmen is working on the track. Transmitter 12 is positioned thirty-live hundred feet up the track from alarm mechanism 14, and is positioned ve hundred feet up the track from alarm mechanism 16.

In operation, when a train passes over the rail to which depression detector 11 is connected, the depression of the rail breaks momentarily a previously closed circuit at the detector 11, as will be later described in detail and as a result of the momentary breaking of this circuit control circuit 13 operates to de-activate tuned radio transmitter 12 which normally sends out radio intelligence that is received by the radio receivers 15 and 17. This deactivation of transmitter 12 is sensed by receivers 15 and 7, and as a result alarm mechanisms 14 and 16 are actuated, as will be described. When alarm mechanism 16 is actuated, it operates a portable whistle sign 21 which is located oit to the side of the track. Whistle sign 21 lights up in a blanking manner to inform the engine man on the train that a gang is working on the track in the area immediately ahead. The engineman thereupon blows the warning whistle of the train which acts as an additional warning to the gang. The primary warning is given to the workmen through the actuation of an audible alarm of alarm mechanism 14 which is set off by the failure of radio receiver 15 to receive a signal from transmitter 12.

Referring to FIGS. 2-5, rail depression detector 11 includes an upright metal support 22 which is adapted to be mounted on the ground beneath a rail and irmly supported on the rail by clamps 23, 24 and clamping rod 25. Support 22 rests on a base 26 which includes steel plates 27, 28 and a layer of insulating material 29. Thus, support 22 is insulated from ground. This is desirable as otherwise, if the other rail of the track also became grounded, the railway signals would be shunted.

A cap 32 is tted over the top portion of support 22, and there is a spring 33 positioned between the top of support 22 and the top of the cap 32. An electrical contact pin 34 is located in the bottom of the cap 32 and is liXed thereto. Fin 34 is adapted to ride up and down within slots 35 formed in support 22, and in so doing maintain contact with the metal support 22. In its normal undepressed position pin 34 is adapted to make contact with an electrical contact 36 which is mounted in suitable insulation in the top of support 22. Contact 36, as seen more clearly in FIG. 9, is the upper turned-over part n.) of a lC-shaped number 37 of good electrical conductivity having one conductor of a pair of leads t3 connected to its lower end. The contact 36 is soldered or otherwise secured to a bolt 12) which is suitably mounted in the upper end of support 22 insulated from both cap 32 and support 22. Spring 33, previously mentioned, tends to extend cap 32 relative to support 22 and in so doing maintains the pin 34 which is xed in cap 32 in close contact up against contact 315 which is held fixed in support 22. Thus, good electrical contact is maintained between pin 34 and contact 36 when the detector is in undepressed condition. An electrical conductor of leads 43 connects a `C-mcrnber 37 with the plug-tip contact of a jack 38 the body of which is grounded to plate 27 and thus to support 22.

Clamp 24 is provided with a warp-around portion 41 which is insulated from clamp 24 and adapted to be clamped around cap 32 by threaded handle 4Z at a point determined by the height of the lower portion of the rail above the ground at the location of the detector. This arrangement provides for adjusting for various distances between the bottom of the rail and the ground surface on which the base 26 rests. When the rail is depressed, as by a train, clamp 24 and the wrap-around portion 41 is depressed and carries with it cap 32. Pin 34, secured to cap 32, moves down in slot 35 and in so doing maintains electrical contact with the lixed metal support 22 at the sides of the slot 35. However, when pin 3d moves downward, electrical contact at surface 36 is opened since surface 36 remains in iiXed position. An instant later the downwardly moving pin 34 makes contact with the side of member 37. lt will be seen, then, that when the. rail is depressed and the pin 34 moves downward, the circuit is broken momentarily at contact 35 and is almost immediately closed at member 37. Member 37 is shaped to receive pin 34 in sliding engagement, thereby to accommodate various amounts of depression of the pin 34. In practice, as the wheels of a train pass over the rail at which the detector 11 is mounted, pin 34 moves successively up and down, breaking and making the circuit a number of times. However, as will be described later, the rst instantaneous breaking of the circuit at the detector 11 is sutiicient to trigger a relay in the control circuit 13 which in turn operates a delay relay which is effective to inactivate the transmitter for a selected period of time, for example, l5 seconds. During his selected period of time, the apparatus is not responsive to the fact that the circuit at the detector 11 is being made and broken successively as the wheels of the train pass by.

Referring to FIG. 6, there is shown control circuit 13 which includes rail detector 11 which is attached to one of the rails of track A, and a second similar detector 11b which is attached to one of the rails of track B. Detector 11 is connected directly (or by a jack and plug as in FIGS. 24) to electrical connectors 43 which terminate in a plug 44. Similarly, the detector 11b is connected to electrical conductors 4311 which terminate in a. plug 44h. Plug t4 is positioned in a jack 45 which is connected to electrical conductor do which leads to a selector switch 47. Plug 44h is positioned in a jack 5b which is connected by leads dbb, 63h, to the selector switch 47. When selector switch 47 is closed, jack 45h is shorted out so that only detector 11 is connected to control circuit 13 so that only trains on track A are sensed by the apparatus. When selector switch 57 is open detectors 11 and 11b are connected in series so that trains on both tracks A and B are sensed by the apparatus.

Control circuit 13 is subdivided into four circuits; a detector circuit, a repeater circuit, a radio controlled circuit, and a restoring circuit.

The detector circuit includes detector 11, electrical conductors 43, plug i-t,'jack 45, conductor da, selector switch 47, a conductor 43, the coii 51 of a reiay 52, conductor 53, conductor 54, a battery 55, conductors 56,

57, switch 53, conductor 61, test button 62, and conductor 63.

The repeater circuit may be traced from the positive side of battery S5 and includes conductors 56, 57, switch 5S, conductor 61, a conductor 6d, an armature 65 of relay 52, a conductor 66, an armature 67 of a repeater relay 68, the coil of relay 65, conductor 71, and conductor 54 back to the negative side of battery 55. Armature 65' normally makes contact with its contact 72, and armature 67 normally makes Contact with its contact 73.

Radio controlled circuit includes conductors 74, 75, an armature 77 of relay 68, a contact 78, and a conductor 79. Armature 77 normally makes contact with contact 78, so that the radio controlled circuit is closed and the transmitter is operating.

Restoring circuit may be traced from the plus side of battery 55, through conductors 55, 57, switch 58, conductor el, test button 62, conductor 63, jack 4S, plug 44, conductors 43 and detector 11, then back from jack 45 through conductor 46, selector switch 47, conductor 4S, a conductor 82, conductor 75, armature 77, the coutact3 of relay 68, a conductor 84, coil S5 of a time delay relay Se, and conductor 54 to the negative side of battery 55.

in operation, control circuit 13 is normally as shown in F16. 6. Upon a train passing to break initially the circuit 43 or 43h at detector 11, coil 51 of relay 52 is deenergiaed to release armature 65 and break the contact with contact 72. This in turn de-energizes the holding circuit and the coil or repeater relay 68. The de-energizing of relay 63 breaks the contact between armature 67 and contact 73. it also breaks the Contact between armature 77 and contact 78 to de-energize the radio controlled circuit and stop the transmiter from operating. it makes Contact between armature 77 and contact S3.

VAs previously explained, as the train passes by that point on the rail to which the detector 11 or 11b is connected, the detector circuit 43 or 43h is opened and closed many times as the weight of the cars is applied to and removed. Each time the detector circuit i3 or 43h is closed, the relay 52 is re-energized and armature 65 makes contact with contact point 72.. However, the circuit remains open at armature o7 and contact point 73. Similarly when the train has passed and the rail has returned to its normal undepressed position, and the circuit at detector 11 is fully restored, the relay 52 is in energized state to close the circuit between armature 65 and 72. However, relay 63 is still de-energized since the circuit is broken between armature d'7 and Contact 73. But since armature 77 is in contact with contact 83, current from battery 55' flows through the time delay coil S5 which is in shunt with relay 52. After a predetermined period of time which may be of the order of from 10 to 20 seconds, typically l5 econds, the heat generated by coil S5 closes the bimetallic contacts 87 of time delay relay 86 to put battery 5S across the coil of relay 68. This circuit maybe traced from the positive side of battery 55, through conductors 56, S7, a'conductor 3S, contacts S7, a conductor 91, through the coil or" relay 65, conductor 71, and conductor 54 to the negative side of battery 55. Thus, the circuit is returned to normal and since arm 77 is again in Contact with Contact 78, the transmitter circuit is again closed and the transmitter operates to send out radio intelligence. We see then that delay relay 86 operates to keep the transmitter 12 oit the air for a selected period of time, such as 15 seconds, after the circuit 43 or 43b has been first opened at the rail detector 11 or 11b and that during this l5-second period it is immaterial whether the circuit at detector 11 or 11b be open or closed. Thus, a warning signal of a reasonable duration, such as l5 seconds, is assured. It will be noted that the detector 11 is so constructed that if at theend of the warning period, of say l5 seconds, the rail is still depressed, as by the wheels of a train sitting motionless at the spot, the circuit 43 or 413i) at the rail detector Yis closed and no 5. warning signal will be issued by the device until the train starts to move. At that time, the circuit at the rail detector will be broken as the wheels of the railway car leave the point at which the detector 11 or 11b is fastened.

Referring now to FIG. 7, there is shown diagrammatically the circuit of alarm mechanism 16 which includes a radio receiver relay 92, and a repeater relay so connected in a circuit that when relay 93 is deenergized battery 94 becomes connected across the whistle signs 21. In operation, when radio receiver 17 is receiving a signal from transmitter 12, the radio receiver relay 92 is energized which in turn energizes repeater relay 93 by connecting battery 94 thereacross. Thus, the whistle signs 21 are disconnected from battery at the open Contact of energized relay 93. When transmitter 12 stops operating, radio receiver relay 92 is de-energized, repeater relay 93 is in turn de-energized and its contact closes to place battery across whistle sign 21.

Referring now to FIG. 8, there is shown alarm mechanism 14 which includes the radio receiver relays 95, 96, relays 97, 98, batteries 101, 102, green lamp 103, red lamp 104, double-pole double-throw power switch 105, audible alarm 106, and audible alarm 107 which is used for testing purposes. In operation, when radio intelligence is being transmitted from transmitter 12, relays 95', 96 are energized and audible alarm 106 is disconnected from battery 101 at the open Contact of relay 98 which is also energized. When radio transmitter 12 ceases operating, relays 95, 96 release, thus opening the circuit through relay 98 and closing the circuit' to connect battery 101 to activate the audible alarm 106.

The term train as herein used includes an engine Without cars, or a motor car, or the like, or any moving vehicle on the tracks, as well as the usual engine pulling a number of railroad cars.

It will be realized that the alarm mechanisms 14 and 16 may be set at any location, as long as they are set at a sucient distance in advance of the train to give the workmen time to clear the track regardless of the speed of the train. Accordingly, although alarm mechanism 14 has been set for purposes of illustration at a point 3500 feet away from detector 11, it may be set at any distance from detector 11 as required in accordance with the authorized speed of trains at the location involved.

Detector 11 may be set on both sides of the gang of Workmen as is indicated in FIG. 1 in the dot-dash lines, so that a warning is given even if the trains should approach on tracks C and D. Obviously, the transmitter and receiver associated with the detectors on tracks C and D would be operated on a different frequency readily distinguishable from that employed by the transmitter and receiver associated with tracks A and B. Additionally, detectors may be placed on both sides of the gang on the same track, so that a warning is given even if a train should approach from the direction counter to the usual direction of traffic. Here again, distinguishing frequencies would be employed. This invention is adapted for use on a single track, and for use on any number of tracks.

It is to be noted that the invention is failsafe. Receivers and 17 are continuously receiving, and transmitter 12 is continuously emitting radio intelligence which is broken by detectors 11 to actuate alarm mechanisms 14, 16. These alarm mechanisms are actuated should anyd thing go wrong with any of the components of the transmitter 12 or receivers 15, 17.

it is to be understood that the form of the invention herewith shown and described is to be taken as a preferred embodiment. Various changes may be made inthe shape, size, and arrangement of parts. For example, equivalent elements may be substituted for those illustrated and described herein, parts may be reversed, and certain features of the invention may be utilized independently of the use of other features, all without departing from the spirit or scope of the invention as defined in the Subjoined claims. Further, although we have referred herein repeatedly to a railroad warning device for detecting movement and warning of the approach ot' a train, it will be understood that the invention is applicable to and be used for detection and warning of the approach of any vehicle operated on a railroad track.

Having described our invention, we claim:

l. A rail detector physically connected to a rail for detecting movement of a train or other rail vehicle along the track by detecting vertical motion of the rail at the point of connection of the detector, said detector including a normally-closed electrical circuit having a fixed and a movable contact for opening momentarily and then closing said electrical circuit during movement of the rail downward from its normal position and for opening momentarily and then closing said electrical circuit during return movement of the rail upward to its normal position, said iixed contact having a horizontal upper stop portion, a vertical lower portion spaced therebelow, and in the intermediate region an oset portion electrically connecting said upper and lower portions and offset laterally from said vertical lower portion, said movable contact being movable vertically between said upper horizontal stop portion and said vertical lower portion without engaging said intermediate portion, said etector including spring means normally holding said movable contact in contact with said horizontal upper stop portion when said rail is in its normal underpressed position, said movable contact being physically coupled to said rail and movable downward and upward through said intermediate region and into and out of Contact with the vertical lower portion as the rail is moved downward and upward.

2. A rail detector as claimed in claim l characterized in that said vertical lower portion of said iixed contact is of substantial length to provide for sliding engagement of said movable contact with said lower portion, thereby to maintain said movable contact in engagement with said lower portion for diierent degrees of depression of said rail.

3. A rail detector as claimed in claim 2 in which said electrical circuit is connected to an electronic control device having switch means adapted to be triggered by an initial momentary opening of said detector electrical circuit for placing said control device in a selected condition, and delay means in said control device adapted to maintain said control device in said selected condition for a preselected period of time independently of closings and openings of said detector electrical circuit during said delay period.

No references cited. LEO QUACKENBUSH, Primary Examiner.

Non-Patent Citations
1 *None
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4325057 *Jun 30, 1980Apr 13, 1982Bishop-Hall, Inc.School bus approach notification method and apparatus
US4713661 *Aug 16, 1985Dec 15, 1987Regency Electronics, Inc.Transportation vehicle location monitor generating unique audible messages
US5924651 *Mar 17, 1998Jul 20, 1999Penza; George GregoryTactile and audible warning system for railroad workers
US8109474 *Nov 27, 2009Feb 7, 2012Bartek Peter MDual ultrasonic train detector
US20110127389 *Nov 27, 2009Jun 2, 2011Bartek Peter MDual ultrasonic train detector
U.S. Classification246/124, 340/507, 246/251, 246/246, 340/539.1, 246/126, 340/666, 200/85.00R, 246/30
International ClassificationB61L1/06, B61L23/00, B61L23/06, B61L1/00
Cooperative ClassificationB61L23/06, B61L1/06
European ClassificationB61L1/06, B61L23/06