US2584234A - Safety device for accessory apparatus on railway trains - Google Patents
Safety device for accessory apparatus on railway trains Download PDFInfo
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- US2584234A US2584234A US708535A US70853546A US2584234A US 2584234 A US2584234 A US 2584234A US 708535 A US708535 A US 708535A US 70853546 A US70853546 A US 70853546A US 2584234 A US2584234 A US 2584234A
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- water
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 19
- 230000003137 locomotive effect Effects 0.000 description 6
- 230000007246 mechanism Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 238000013459 approach Methods 0.000 description 3
- 230000002459 sustained effect Effects 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000007688 edging Methods 0.000 description 2
- 230000001939 inductive effect Effects 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000001143 conditioned effect Effects 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000004044 response Effects 0.000 description 1
Images
Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
- B61L1/00—Devices along the route controlled by interaction with the vehicle or train
- B61L1/20—Safety arrangements for preventing or indicating malfunction of the device, e.g. by leakage current, by lightning
Definitions
- This invention relates to protective devices for assuring a safe conditiorr of accessory devices on railway trains on approach to particular portions of the track. The result is efiected by interlocking the accessory device with a train control device which normally responds totrackside signal'scontrolling train movement.
- the interlock is betweenthe accessory device and the acknowledging or forestalling device (forming part of most: train control systems)- which permits the engineer to pass a signal set against him, pro-- vided he. operates the. acknowledging device at the proper time.
- The. interlock is such that if the accessory device is in an unsafe condition operation of the acknowledging device is inhibited.
- a special trackside element is installed at the desired point on the track. This is an independent unit not related to the trackside signal system which controls train movement,
- the water pan. extends between the track rails for several hundred yardsand. endsin a. cam or ramprdesigned. to ensure. that the scoop will rise overtheleaving endof the pan in the event that the engineer is slow in operatingthe control.
- the scoop is hinged to the tender: and may be loweredby the engineer sothat its'leading end dips into water in. the pan and conducts water up. into. the tank inthe. tender by an inertia re action.
- The: engineer is supposed to retract the scoop when, the. tank is filled, and in. any event beforethe leaving end. of the. pan. is; reached.
- the scoop is motor actuated, and. failure; to-lift the scoop to its fully retracted position, can: oc cur as the; result of. some. mechanical failure. withoutfault of. the; engineer, and. withoutknowh edge; by the: engineer that such. failure has occurred.
- the invention contemplates disabling. the acknowb edging; device except. when. the scoop is. fully retracted.
- a trackside unit. compels acknowledgement as the locomotive leaves the pan and, in the; case of: a;- water scoop installation-,7 would be set. always. to; actuate. the. train control.
- Most train control systems includev a timing de.- vice designed to prevent abuse of the acknowl-- edging device.
- a timing de.- vice designed to prevent abuse of the acknowl-- edging device.
- the acknowledging. device allows the acknowledging. device to be effective for fifteen seconds, so. that the engineer can acknowledge as he approachesv the signal;
- the trackside unit may be located a short distance beyondv the leaving end of the pan, so thatv the engineer will have timeto acknowledge after the latestv practicable retraction of the scoop.
- circuit diagram in applicants drawing. is based on Fig. 32 of: Handbook No. 6 and Fig. 9 of Pamphlet B 326. The same diagram appears in each and. the reference letters andnum. bers are used on the. application drawing.
- Fig. 1 shows portions of a locomotive tender with the waterscoop. in. elevation in. its lowered position.
- the train control circuits are shown in diagram.
- Fig. 2 is a view similar to a portion of Fig. l but showing the water'scoop in its normal, raised position.
- Fig. 3- is a plan view of the track, drawn on a small scale. and indicating' an acceptable arrangement of the end of. the water tank (with its ramp) and the trackside element used according to the invention.
- a control valve 26.: is provided. to enable 3 the engineer to operate this motor Iull stroke in either direction as desired.
- a second arm I9 of the three-armed lever swings between stops 2
- a third arm 28 of the three-armed lever reacts upward in a counter-balancing spring assembly generally indicated at 29. This is sustained by a pad 3I carried by the underframe I3.
- the spring assembly biases the three-armed lever to the position shown in Fig. 2 in which the water scoop is raised. In that position the open end of the scoop is protected by a shield 32 sustained by the brackets which carrystop 2
- the mechanism so far described will be reco nized as a commercial form of water scoop. It coacts with a water pan 33 arranged between two track rails II as shown in Fig. 3.
- a cam rail or ramp 34 is located at the leaving end of pan 33 to lift the scoop over the end of the pan if the engineer is late in retracting it.
- a limit switch which produces the interlock with the acknowledging or forestalling circuit to be described.
- a plunger or stem 36 Guided in the housing is a plunger or stem 36 urged downward by a coil compression spring 31.
- the stem carries two contactors 38, 39 which bridge corresponding pairs of bow contacts only when the stem is forced up by arm I9.
- the limit switch is in effect two switches operated in unison. Each controls a corresponding part of the acknowledging (forestalling) circuit in such a way that the circuit is interrupted unless arm I9 is against stop 22, at which time the scoop is fully retracted (see Fig. 2).
- FIG. 1 A typical train control circuit capable of control by a limit switch such as 35 is diagrammed in Fig. 1, is fully described in the publications mentioned, and being familiar to persons skilled in the art, will be only briefly described.
- the three relays RI, R2 and R3, as well as the electro-pneumatic valve E. P. V., are energized from the headlight generator G.
- the circuit through the electro-pneumatic valve from the generator is wire B32, contact 3 of relay R2, wire P3, contact 6 or I of relay R3, wire P2, contact 8 of the reset contactor, contact Z, wire P4A, the electro-pneumatic valve and wire C to the generator.
- Relay RI is energized through wire B32, contact 3, wire P3, contact 6 or I, wire P2, contact I, wire SI, the secondary coil S of the receiver, the coil of relay RI, the ballast lamps LL and primary coil P of the receiver to wire C.
- Relay R2 is energized through wire B32, contact 3, wire P3, contact 6 or I, wire P2, contact 2 and coil R2 to wire C.
- Relay R3 is energized through wire B32, contact 3, wire P3, contact 6 or 1, wire P2, relay coil R3, the ballast lamps LL, the primary coil P of the receiver and wire C.
- the relay R2 is also deenergized when contact 2 opens; this in turn causes contact 3 to open and contacts 4 and 5 to close.
- the opening of contact 3 causes relay R3 to be deenergized, and its contacts 6 and I will open; this results in the electro-pneumatic valve being deenergized to produce a brake application.
- the limit switch 35 is interposed so that one of its contactors 39 controls the circuit also controlled by the switch X, and the other of its contacts 38 controls the circuit also controlled b the switch Y.
- the switches X or Y can complete its circuit unless the water scoop is so fully retracted that'the switch 35 is in the circuit closing position of Fig. 2.
- the train control circuit is customarily located on the locomotive and the water scoop is customarily located on the tender. Therefore, the interlocking circuits must lead to the tender.
- Jumpers, indicated generally at 42, are provide between the locomotive and tender.
- can be a simple bar of 'soft iron without any choke coil such as that customarily used with trackside elements in the G. R. S. system.
- the acknowledging contactor of the G. R. S. system cannot be held closed for more than fifteen seconds because a clockwork arrangement forming part of the control will open the switch'Z after the acknowledging contactors have been closed for the period stated.
- This provision is for the purpose of permittin the engineer to acknowledge a signal as he approaches it without permitting abuse of the acknowledging mechanism. Because of this arrangement it is advisable to locate the trackside inductor 4
- an interlocking switch 35 or its equivalent could be arranged to be operated by any train carried piece of accessory apparatus i which has a safe position and is potentially dangerous unless it is in that position. Furthermore, the function of the switch 35 is to disable the acknowledgin mechanism, whatever that may be.
- the invention is applicable to a wide range of accessory apparatus, and to specifically different types of train control, in lieu of the particular pieces of apparatus here described to illustrate the broad principles of the invention.
- a railway track a rail vehicle which runs thereon; an automatic control system including signal-set trackside elements, coactive vehicle-carried elements, normally responsive thereto to stop the vehicle, and a vehicle-carried acknowledging device which i 6 when actuated serves to prevent vehicle-stopping response of said system; a vehicle-carried accessory device having a safe position and at least one potentially dangerous position; a controller adapted to be manually set by the operator of the vehicle alternatively in two positions, in one of which it causes said device to move to, and in the other of which it causes said device to move from said safe position; means actuated by said accessory device and effective in all positions thereof except said safe position to suspend the functioning of said acknowledging device; and a trackside element located near a point on the track at which the operator should shift said controller to cause said device to move to safe position, said trackside element being continuously conditioned to actuate the vehiclecarried elements of the control system.
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- Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Mechanical Engineering (AREA)
- Train Traffic Observation, Control, And Security (AREA)
Description
L. K. SILLCQX 2,584,234
SAFETY DEVICE FOR ACCESSORY APPARATUS ON RAILWAY TRAINS Feb.5, 1952.
Filed Nov. 8, 1946 Lewis K.Si11cox (I ttornegs Patented Feb. 5, 1 952 NIT OFFICE.
SAFETY DEVICEEOR ACCESSORY APPA- nA'rUs on RAILWAY TRAINS Lewis K. Sillcox; Watertown, N. Y., assignor to The-.New-Yorlc Air Brake Company, a corporation of New-Jersey ApplicatibnNovember 8, 1946, Serial No. 708,535
1 Glaim. l I This invention relates to protective devices for assuring a safe conditiorr of accessory devices on railway trains on approach to particular portions of the track. The result is efiected by interlocking the accessory device with a train control device which normally responds totrackside signal'scontrolling train movement.
To bring about the desired result the interlock is betweenthe accessory device and the acknowledging or forestalling device (forming part of most: train control systems)- which permits the engineer to pass a signal set against him, pro-- vided he. operates the. acknowledging device at the proper time. The. interlock is such that if the accessory device is in an unsafe condition operation of the acknowledging device is inhibited. To compel operation of the iorestalling device a special trackside elementis installed at the desired point on the track. This is an independent unit not related to the trackside signal system which controls train movement,
As-animportant and typical embodiment of the invention i-twillbedescribed as embodied to ensure that a. locomotive leaving a water pan carries. its water scoopin. completely retracted position.
The water pan. extends between the track rails for several hundred yardsand. endsin a. cam or ramprdesigned. to ensure. that the scoop will rise overtheleaving endof the pan in the event that the engineer is slow in operatingthe control. The scoop is hinged to the tender: and may be loweredby the engineer sothat its'leading end dips into water in. the pan and conducts water up. into. the tank inthe. tender by an inertia re action. The: engineer is supposed to retract the scoop when, the. tank is filled, and in. any event beforethe leaving end. of the. pan. is; reached. The scoop is motor actuated, and. failure; to-lift the scoop to its fully retracted position, can: oc cur as the; result of. some. mechanical failure. withoutfault of. the; engineer, and. withoutknowh edge; by the: engineer that such. failure has occurred.
To guard against accident in the event of, such a failure or of. negligent manipulation, the invention contemplates disabling. the acknowb edging; device except. when. the scoop is. fully retracted. A trackside unit. compels acknowledgement as the locomotive leaves the pan and, in the; case of: a;- water scoop installation-,7 would be set. always. to; actuate. the. train control.
This: last: condition is not: indispensable for all installations; because certain accessory devices might. require; checking: only at; certain times;
ill
Most train control systems includev a timing de.- vice designed to prevent abuse of the acknowl-- edging device. For example, one here illustrated allows the acknowledging. device to be effective for fifteen seconds, so. that the engineer can acknowledge as he approachesv the signal; With such an arrangement the trackside unit may be located a short distance beyondv the leaving end of the pan, so thatv the engineer will have timeto acknowledge after the latestv practicable retraction of the scoop.
While the principle; could; be explained. by simple diagrams, a commercial installation is i1- lustrated in the drawing. This involves; merely: byway of example, a: known water scoop mechanism with a dual. limit switch attached and inter.- posed in the acknowledging-circuits of the General Railway Signal: Company's Intermittent Train Control.
To render an extremely detailed; description or this well known. commercial train control system unnecessary, there are filed. with this application the: following publications G. R. S. Automatic Train Control; Intermittent Inductive Auto-Manual System. Handbook No. 6, second; edition (copyright 1928:) and Pamphlet 3-526, third edition (copyright 1926).
The circuit diagram in applicants drawing. is based on Fig. 32 of: Handbook No. 6 and Fig. 9 of Pamphlet B 326. The same diagram appears in each and. the reference letters andnum. bers are used on the. application drawing.
In the drawings:
Fig. 1 shows portions of a locomotive tender with the waterscoop. in. elevation in. its lowered position. The train control circuits are shown in diagram.
Fig. 2 is a view similar to a portion of Fig. l but showing the water'scoop in its normal, raised position.
Fig. 3- is a plan view of the track, drawn on a small scale. and indicating' an acceptable arrangement of the end of. the water tank (with its ramp) and the trackside element used according to the invention.
Referring. first to Fig. 1 a track. rail is indicated at i 1-, a. tender Wheel at 1.2 and a. portion of the tender underframe at 13. Hung from. the underframe l3 isthe bracket. It which. supports thev fulcrum, iii of. a three-armed lever, one of. whose arms; is is. connected by link. II with the piston rodof a, double-acting air motor generally indicated by the. numeral it applied to=its-. cylin-- den. A control valve 26.: is provided. to enable 3 the engineer to operate this motor Iull stroke in either direction as desired.
A second arm I9 of the three-armed lever swings between stops 2| and 22 sustained by the frame [3. Arm I9 is connected by link 23 and chain 24, respectively, to two articulated hollow sections 25 and 26 of the water scoop. Section 26 is hinged to the hollow bracket 21, through which scooped water is delivered to the water tank (not shown).
A third arm 28 of the three-armed lever reacts upward in a counter-balancing spring assembly generally indicated at 29. This is sustained by a pad 3I carried by the underframe I3. The spring assembly biases the three-armed lever to the position shown in Fig. 2 in which the water scoop is raised. In that position the open end of the scoop is protected by a shield 32 sustained by the brackets which carrystop 2|.
The mechanism so far described will be reco nized as a commercial form of water scoop. It coacts with a water pan 33 arranged between two track rails II as shown in Fig. 3. A cam rail or ramp 34 is located at the leaving end of pan 33 to lift the scoop over the end of the pan if the engineer is late in retracting it.
Mounted above stop 22 is the housing 35 of a limit switch which produces the interlock with the acknowledging or forestalling circuit to be described. Guided in the housing is a plunger or stem 36 urged downward by a coil compression spring 31. When the plunger is at its lower limit of motion its lower tip projects beyond stop 22 in position to be forced up by arm I9 as the arm closely approaches stop 22. The stem carries two contactors 38, 39 which bridge corresponding pairs of bow contacts only when the stem is forced up by arm I9. Thus the limit switch is in effect two switches operated in unison. Each controls a corresponding part of the acknowledging (forestalling) circuit in such a way that the circuit is interrupted unless arm I9 is against stop 22, at which time the scoop is fully retracted (see Fig. 2).
A typical train control circuit capable of control by a limit switch such as 35 is diagrammed in Fig. 1, is fully described in the publications mentioned, and being familiar to persons skilled in the art, will be only briefly described.
The three relays RI, R2 and R3, as well as the electro-pneumatic valve E. P. V., are energized from the headlight generator G. The circuit through the electro-pneumatic valve from the generator is wire B32, contact 3 of relay R2, wire P3, contact 6 or I of relay R3, wire P2, contact 8 of the reset contactor, contact Z, wire P4A, the electro-pneumatic valve and wire C to the generator. Relay RI is energized through wire B32, contact 3, wire P3, contact 6 or I, wire P2, contact I, wire SI, the secondary coil S of the receiver, the coil of relay RI, the ballast lamps LL and primary coil P of the receiver to wire C. Relay R2 is energized through wire B32, contact 3, wire P3, contact 6 or I, wire P2, contact 2 and coil R2 to wire C. Relay R3 is energized through wire B32, contact 3, wire P3, contact 6 or 1, wire P2, relay coil R3, the ballast lamps LL, the primary coil P of the receiver and wire C.
When the receiver passes over an open circuited trackside inductor such as 4! (Fig. 3), an electromotive force is momentarily induced in the coil S and of opposite polarity to that of the generator. This results in a sudden drop in voltage and current flow at relay RI and contacts I and 2 open. Since the circuit of relay not reenergized after the inductor is passed.
The relay R2 is also deenergized when contact 2 opens; this in turn causes contact 3 to open and contacts 4 and 5 to close. The opening of contact 3 causes relay R3 to be deenergized, and its contacts 6 and I will open; this results in the electro-pneumatic valve being deenergized to produce a brake application.
In order to prevent a brake application the engineman must move the handle of the acknowledging contactor to closed position before the receiver passes over the wayside element. In this position contacts X and Y are closed and a circuit is completed through wire B32, the whistle valve "WV, contact X, contact 6 or I, wire P2, coil of relay R3, ballast lamps LL, primary P of the receiver, and wire C. This forms a circuit through the coil of relay R3 by-passing the contacts of relays RI and R2. With relay R3 energized, the velectr c-pneumatic valve will remain energized and no brake application occurs.
According to the invention the limit switch 35 is interposed so that one of its contactors 39 controls the circuit also controlled by the switch X, and the other of its contacts 38 controls the circuit also controlled b the switch Y. Thus, neither of the switches X or Y can complete its circuit unless the water scoop is so fully retracted that'the switch 35 is in the circuit closing position of Fig. 2.
The train control circuit is customarily located on the locomotive and the water scoop is customarily located on the tender. Therefore, the interlocking circuits must lead to the tender. Jumpers, indicated generally at 42, are provide between the locomotive and tender.
Operation and Y willbe operative because the switch35 will be closed. Consequently, when the locomotive passes the trackside inductor 4| the train control device will not be operated and no brake application will be produced.
However, if the water scoop is not completely retracted so that the switch '35 is open, neither of the two forestalling switches X or Y can complete the forestalling circuit. Consequently, the train control will operate and produce a brake application. This will stop the train and warn the engineer that the water scoop apparatus has not functioned properly.
'-'Since this protection is desirable at all times the trackside unit 4| can be a simple bar of 'soft iron without any choke coil such as that customarily used with trackside elements in the G. R. S. system.
In any case where the protective feature would be needed at certain times and not at others the conventional trackside element with choke coil and some controlling mechanism therefor could be used.
As is well understood the acknowledging contactor of the G. R. S. system cannot be held closed for more than fifteen seconds because a clockwork arrangement forming part of the control will open the switch'Z after the acknowledging contactors have been closed for the period stated.
This provision is for the purpose of permittin the engineer to acknowledge a signal as he approaches it without permitting abuse of the acknowledging mechanism. Because of this arrangement it is advisable to locate the trackside inductor 4| a short distance beyond the leaving end of the pan 33 so that if the engineer lifts the scoop just before he leaves the end of the pan he will still have time to acknowledge the trackside unit 4|.
As suggested, an interlocking switch 35 or its equivalent could be arranged to be operated by any train carried piece of accessory apparatus i which has a safe position and is potentially dangerous unless it is in that position. Furthermore, the function of the switch 35 is to disable the acknowledgin mechanism, whatever that may be.
By interposing the interlock between the accessory device and the acknowledging device it is possible to avoid any change in, or interference with, the normal functions of the train control.
Obviously, therefore, the invention is applicable to a wide range of accessory apparatus, and to specifically different types of train control, in lieu of the particular pieces of apparatus here described to illustrate the broad principles of the invention.
What is claimed is:
The combination of a railway track; a rail vehicle which runs thereon; an automatic control system including signal-set trackside elements, coactive vehicle-carried elements, normally responsive thereto to stop the vehicle, and a vehicle-carried acknowledging device which i 6 when actuated serves to prevent vehicle-stopping response of said system; a vehicle-carried accessory device having a safe position and at least one potentially dangerous position; a controller adapted to be manually set by the operator of the vehicle alternatively in two positions, in one of which it causes said device to move to, and in the other of which it causes said device to move from said safe position; means actuated by said accessory device and effective in all positions thereof except said safe position to suspend the functioning of said acknowledging device; and a trackside element located near a point on the track at which the operator should shift said controller to cause said device to move to safe position, said trackside element being continuously conditioned to actuate the vehiclecarried elements of the control system.
LEWIS K. SILLCOX.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 1,114,813 shreve Oct. 2'7, 1914 2,190,505 Smith Feb. 13, 1940 2,216,713 Wait Oct. 1, 1940 OTHER REFERENCES G-R-S Automatic Train Control, Intermittent Inductive Auto-Manual System. Handbook No. 6, 2d ed. (1928) copy in file.
Pamphlet B-526, 3d ed. (1927) of G-R-S Automatic Train Control; copy in file.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US708535A US2584234A (en) | 1946-11-08 | 1946-11-08 | Safety device for accessory apparatus on railway trains |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US708535A US2584234A (en) | 1946-11-08 | 1946-11-08 | Safety device for accessory apparatus on railway trains |
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US2584234A true US2584234A (en) | 1952-02-05 |
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US708535A Expired - Lifetime US2584234A (en) | 1946-11-08 | 1946-11-08 | Safety device for accessory apparatus on railway trains |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3021423A (en) * | 1957-05-13 | 1962-02-13 | Westinghouse Air Brake Co | Broken railway wheel flange detectors |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1114813A (en) * | 1913-01-11 | 1914-10-27 | Chicago Safety Appliance Company | Safety-switch. |
US2190505A (en) * | 1938-11-19 | 1940-02-13 | Gen Railway Signal Co | Automatic train control system for railroads |
US2216713A (en) * | 1938-10-08 | 1940-10-01 | Walt William Bell | Train control system |
-
1946
- 1946-11-08 US US708535A patent/US2584234A/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1114813A (en) * | 1913-01-11 | 1914-10-27 | Chicago Safety Appliance Company | Safety-switch. |
US2216713A (en) * | 1938-10-08 | 1940-10-01 | Walt William Bell | Train control system |
US2190505A (en) * | 1938-11-19 | 1940-02-13 | Gen Railway Signal Co | Automatic train control system for railroads |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3021423A (en) * | 1957-05-13 | 1962-02-13 | Westinghouse Air Brake Co | Broken railway wheel flange detectors |
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