US3544960A - Railway safety apparatus - Google Patents

Railway safety apparatus Download PDF

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Publication number
US3544960A
US3544960A US724089A US3544960DA US3544960A US 3544960 A US3544960 A US 3544960A US 724089 A US724089 A US 724089A US 3544960D A US3544960D A US 3544960DA US 3544960 A US3544960 A US 3544960A
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signal
derail
signalling
track
contacts
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US724089A
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Brice E Hayes
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Hayes Track Appliance Co
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Hayes Track Appliance Co
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B61RAILWAYS
    • B61LGUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
    • B61L7/00Remote control of local operating means for points, signals, or trackmounted scotch-blocks
    • B61L7/06Remote control of local operating means for points, signals, or trackmounted scotch-blocks using electrical transmission
    • B61L7/08Circuitry
    • B61L7/081Direct line wire control

Definitions

  • a compact housing mounted along the roadbed encloses a remote controlled operating mechanism for pivoting a blue flag signal and lamp between a horizontal standby position over the roadbed and an upstanding signalling position. Readback indications are provided at the remote location, and an indication that the signal is up is prevented untl both the operating mechanism and the signal have moved. A lamp on the signal is energized independently of signal movement.
  • the signal may be used with a derail, in which case it is operated only in response to completion of the operation of the derail.
  • the present invention relates to safety apparatus for railroads and more particularly to an improved remote controlled signal, which may be a blue flag signal, and also to improved apparatus including both a signal and an appliance such as a derail.
  • an improved remote controlled signal which may be a blue flag signal
  • improved apparatus including both a signal and an appliance such as a derail.
  • a blue flag or blue flag signal as the term is used in the railroad industry and in the present specification and claims is a signal.used on railroad track to protect humans working on or about the track and to protect equipment on the track.
  • a blue flag signal placed on a track is a warning that the track must not be entered and that equipment on the track must not be moved.
  • a blue flag signal may comprise a blue flag, but a blue sign orpanel supported on a staff may be used in place of a flag, and the term blue flag applies to either type.
  • Many railroads require personnel who repair, inspect or work about a car to protect the track with a blue flag.
  • blue flags are often used to protect tank cars, camp cars and the like. Customarily blue flags have been placed manually by workmen or other railroad personnel.
  • Blue flags may be used in conjunction with an appliance such as a derailing device more securely to protect workers or equipment on the track. If a derail is placed in derailing position on the track adjacent a blue flag, the track is protected against damage caused by equipment running through the blue flag should the flag be ignored or unnoticed. In the past, manually operated derails have been used with blue flag signals. This arrangement is inconvenient, especially in locations such as classification and departure tracks, loading and unloading facilities, repair shops and the like wherein protection for workers is required at frequent intervals and the derail must be moved on and off the rail frequently.
  • An object of the present invention is to provide improvements in railway safety apparatus.
  • Another object of the invention is to provide a new and improved remote controlled signal which may be a blue flag signal although principles of the invention could be applied to signals of other types.
  • Another object is to provide an improved remote controlled signal which is inexpensive, convenient and safe.
  • Another object is to provide a signal easily installed at any desired location on existing track without modification of the track or roadbed and which does not interfere with use of the track or with visibility along the track.
  • a further object is to provide a blue flag signal particularly suited for use with a remote controlled appliance such as a derail.
  • a further object of the invention is the provision of a remote controlled signal including means for providing a readback indication of signal position only when the signal itself as well as the signal operating mechanism have assumed the selected positions.
  • Another object of the invention is to provide improved safety apparatus including an appliance such as a derail in conjunction with a signal such as a blue flag signal and having particular utility where frequent movements of the appliance and signal are desired.
  • Another object is to provide an arrangement including an appliance and a signal for indicating the position of the appliance wherein the signal is operated only in response to completion of movement of the appliance so that the signal cannot move independently of the appliance.
  • a novel signalling apparatus including an operating mechanism capable of remote control and a signal movable between positions by the operating mechanism.
  • the signal may be a blue flag signal and is movable between an inactive or standby position in which neither the signal nor the operating mechanism interferes with use of the track and an active or signalling position in which the signal is located above the track rails.
  • the operating mechanism is enclosed in a low housing supported between adjacent ties and between or to the side of the rails, and the signal is carried by a support staff pivotally mounted on the housing. In the inactive position, the staff extends horizontally from the housing and lies flat on or close above the roadbed. In the signalling position, the staff is pivoted upwardly to raise the signal prominently into view.
  • the signal may be operated from a remote location so that manual placement and removal is avoided.
  • the operating mechanism includes an actuating element driven by an electric motor or the like between positions for raising and lowering the signal in response to operation of a control switch or controller.
  • One feature of the invention resides in a novel arrangement for providing readback indications of the signal position and for preventing a false indication that the signal is in the active or signalling position. A readback indication to this effect is prevented until a limit switch is operated by the actuating element and until a position responsive switch is operated by actual movement of a signal into the signalling position.
  • the invention further provides a novel safety apparatus including the signalling apparatus in combination with a remote controlled appliance such as a derail.
  • a remote controlled appliance such as a derail.
  • the blue flag signal used with a derail produces a highly effective and convenient means for protecting the track.
  • the blue flag signal is moved to its active or signalling position thus producing a warning and an indication of the presence of the derail.
  • the signal is operated not by the operating mechanism for the derail, but by its own operating mechanism which is actuated only after completion of movement of the derail.
  • FIG. 1 is a perspective view of a signalling apparatus embodying the present invention
  • FIG. 2 is an enlarged, perspective view of the housing of the apparatus of FIG. 1 with the cover removed to reveal the operating mechanism;
  • FIG. 3 is a greatly enlarged, fragmentary, sectional view in part of the apparatus of FIG. 1 with the signal in the signalling or active position;
  • FIG. 4 is a schematic diagram illustrating a control circuit for the apparatus of FIG. 1;
  • FIG. 5 is a plan view of the apparatus of FIG. 1 used with a remote controlled railway appliance.
  • FIG. 6 is a fragmentary, schematic diagram illustrating portions of a circuit for controlling the apparatus of FIG. 5.
  • the signalling apparatus includes an operating mechanism generally designated as 12 (FIG. 2) enclosed in a housing 14, together with a signal generally designated as 16 supported on a staff 18 pivotally mounted upon the housing 14.
  • the operating mechanism 12 is controlled by a remote control unit generally designated as 20 and illustrated only in FIG. 4 in order to move the staff 18 and signal 16 between an inactive or standby position shown in full lines in FIG. 1 and a signalling or active position shown in broken lines in FIG. 1.
  • the signal 16 may be a blue flag signal and includes a sign or panel 22 supported on the staff 18, which sign may be of a blue color and may carry a suitable legend in a contrasting color.
  • the signal 16 also includes a lamp 24 supported in a socket 26 mounted on the end of staff 18, which lamp may also be blue in color.
  • a blue flag signal is customarily displayed above and between or to the side of the track rails where it is highly visible from equipment moving along the track.
  • Arrangements have been devised in the past including an operating mechanism mounted in a large, upstanding housing located to the side of the track rails for pivoting a blue flag signal in a horizontal plane well above the grade level.
  • Such arrangements have been bulky, expensive, and inconvenient to install since in many locations they require modification of the roadbed or the like. In addition, such arrangements may be dangerous since the signal when moving in a horizontal plane over the track can strike an unsuspecting track worker.
  • the present invention provides a compact and simple signalling apparatus which can easily be installed in any desired location in existing track without modification thereof, which does not interfere in any way with use of the track or visibility along the track, and which is not dangerous to railroad personnel.
  • the apparatus 10 is illustrated as installed in track including running rails R and crossties C.
  • the housing 14 is compact in shape and low in silhouette and is mounted between adjacent ties and between the track rails. It should be understood that if desired, the device could be mounted to the side of the rails. The low, compact housing in no way interferes with use of the track or with visibility along the track.
  • the apparatus In the standby condition of the signal, the apparatus is inconspicuous and unobstructive.
  • the signal pivots with respect to the housing in a vertical plane, and in the standby position illustrated in full lines in FIG. 1 the staff 18 extends horizontally from the housing 14 so that the staff and signal lie fiat immediately over the roadbed.
  • the signal 16 In this position, the signal 16 is out of sight and provides 4 no obstruction to use of or visibility along the track.
  • the staff 18 and the signal 16 In its signalling position, the staff 18 and the signal 16 are pivoted upwardly to the position shown in broken lines in FIG. 1 wherein the panel 22 and lamp 24 are disposed well above grade level in a highly conspicuous location.
  • the apparatus 10 is safe because a workman could not be in the path of movement of the signal without being aware of the signal.
  • the housing 14 may be fabricated of metal or the like and includes an open upper wall closed by means of a cover 28 to protect the operating mechanism 12.
  • the housing includes a pair of side flanges 30' for attaching the housing to adjacent ties C by means of lag screws or suitable fasteners 32.
  • the housing may be easily and quickly installed at any desired location in existing track without special preparation or modification.
  • Movement of the signal 16 between its active and inactive positions is accomplished by pivotal or rotational movement in a vertical plane of the staff 18 with respect to the housing 14.
  • the end of the shaft is connected to a clamp 34 fixed on a shaft 36 extending through the wall of the housing 14 and journaled for rotation in a bearing member 38. Movement is imparted to the shaft 18 and signal 16 by means of an actuating element or arm 40 attached to the shaft 36 within the housing 14.
  • the operating mechanism 12 enclosed within the housing 14 may be of any suitable type known to those skilled in the art.
  • the operating mechanism 12 includes an electric motor 42 for rotating a screw element 44, together with a nut assembly 46 pivotally connected to the arm 40.
  • the electric motor 42 can be rotated in two directions whereupon a drive shaft 48 of the motor connected to the screw element 44 by means of a coupling 50 rotates the screw element to move the nut assembly 46 axially along the screw element between a pair of stop members 52 and 54. Since the nut assembly 46 is pivotally mounted to a point on the arm 40, the motor 42 and screw element 44 are mounted for pivotal movement on a mounting plate 56 by means of a pivot pin assembly 58.
  • the nut assembly 46 may be of any suitable construction and preferably is capable of a free wheeling operation after engagement of the nut assembly with one of the stop members 52 and 54 so that the motor shaft 48 and screw element 44 may continue to rotate.
  • the nut assembly and screw element are preferably arranged so that they provide a reversible drive translating means so that the signal staff 18 can be manually moved between positions without declutching of the drive in the event of a power failure.
  • the nut assembly and screw may be of the type known as the Roton, of which a further description may be obtained from US. Pat. No. 3,099,168 and other patents issued to The Anderson Company, a corporation of Indiana.
  • a pair of limit switches 60 and 62 are mounted within the housing 14 and are operated near the ends of the range of movement of the operating mechanism.
  • a switch operating plate 64 is attached to the arm 40 which operates the switches 60 and 62 as the nut assembly nears the stop members 52 and 54. If desired the switches may be operated shortly before engagement of the nut assembly 46 with the stop members, whereupon the momentum of the operating mechanism serves to carry the nut assembly against the stop member even though the motor 42 is deenergized.
  • control circuit 66 for controlling the operation of the signalling apparatus 10.
  • the control circuit 66 of the apparatus 10 is connected by a suitable five conductor cable or the like 67 with the remote control unit 20 located any desired distance from the signalling apparatus 10.
  • the apparatus could be installed on a classification or departure track in a railroad yard, and the control unit could be located in a control tower.
  • the control circuit 66, as well as the unit 20 are supplied with power from a pair of power supply terminals 68 and 69.
  • the control unit 20 includes an electric switch or controller 70 movable between two positions corresponding to the standby and signalling positions of the signal 16, and connected to the control circuit 66 by two conductors 72 and 74 of the cable 67. Closure of a first set of controller contacts 70a results in movement of the signal 16 to the standby condition illustrated in FIGS. 1, 2 and 4, while closure of contacts 70b results in movement of the signal 16 to its signalling position.
  • the unit 20 also includes a pair of indicator lamps 76 and 78 connected to the circuit 66 by cable conductors 80 and 82 for indicating to the operator the position of the signal.
  • the remaining cable conductor 83 is a power supply cable connected to the power supply terminal 69.
  • Movement of the signal 16 in both directions is accomplished by bidirectional or reversible operation of the motor 42.
  • the motor includes an armature winding 84 as well as a field Winding 86, these being illustrated in FIG. 4.
  • a pair of motor control relays 88 and 90 serve, in combination with the limit switches 60 and 62, to control both the energization and direction of operation of the motor.
  • the signal is at rest in the inactive or standby position shown in FIGS. 1 and 2, and the motor 42 is disconnected by the relays 88 and 90.
  • the limit switch 60 which comprises a double pole, double throw switch, is operated by the actuating element or arm 40 and plate 64 to open a pair of sets of normally closed contacts 601; and 60b, and to close a normally open set of contacts 60c.
  • the indicator lamp 76 is energized by a circuit including conductor 83, conductor 80, and contacts 600 of the limit switch 60 in order to provide an indication at the remote location that the signal is in the standby condition.
  • the operator located at the remote point can move the signal to its active or signalling position by operation of controller 70 to its alternate position to open contacts 70a and close contacts 70b.
  • the motor 42 is operated to raise the signal, the signal lamp 24 is energized, the indicator lamp 76 is extinguished and, providing the signal operates properly, the indicator lamp 78 is energized to provide an indication that the apparatus has obtained its active or signalling position.
  • closure of contacts 70b completes a circuit for energization of the motor control relay 88, this circuit including conductor 83, contacts 70b, conductor 74, and a normally closed set of contacts 62a of the limit switch 62.
  • the relay 88 When the relay 88 is energized, a normally closed set of relay contacts 88a are opened and a normally open set of contacts 88b are closed. Consequently, the motor armature 84 is connected in series with the field winding 86 across the power supply terminals 68 and 69.
  • the reversible motor 42 is designed in known manner so that it rotates in a direction for moving the nut assembly 46 along the screw member 44 away from the stop member 52 and limit switch 60.
  • An important feature of the invention resides in the provision of a novel arrangement for assuring that the signal lamp 24 is energized even if the signal 16 is not fully raised, and also for preventing a readback indication indicating satisfactory operation of the apparatus unless the signal 16 is actually moved to the active position.
  • the plate 64 releases the limit switch 60 to close the normally closed set of contacts 60b, and complete a circuit for energization of the signal lamp 24 across the power supply terminals 68 and 69.
  • the signal lamp 24 is accordingly energized shortly after operation of the controller 70 to provide a danger indication independently of whether or not the signal 16 is moved all the Way to its signalling position, so that at least a partial signal is provided.
  • the circuit for energizing the indicator lamp 78 includes a position responsive switch 92 in series with the contacts 60b of the limit switch 60.
  • the switch 92 may comprise a mercury contact switch mounted within the lamp housing 26 by means of a bracket 94, although other types of switch could be used.
  • the switch 92 is closed only in response to movement of the housing 26, and thus of the signal 16, to the upright signalling or active position, and a false readback indication is prevented. This is an improvement over prior art arrangements wherein operation of a limit switch by the operating mechanism provides a readback regardless of the actual signal position.
  • a circuit including contacts 60b, switch 92, conductor 82 and conductor 83 energizes the indicator lamp 78.
  • Operation of the signalling apparatus 10 in the reverse direction is also accomplished by movement of the controller 70.
  • Closure of contacts 70a completes a circuit for energization of the motor control relay through conductor 72 and contacts 60a of the limit switch 60.
  • a normally closed set of relay contacts 90a are opened and contacts 90b are closed, and the armature 84 and field Winding 86 of the motor 42 are connected in series across the power supply.
  • the polarity of the field winding 86 is reversed by operation of the relay 90 rather than the relay 88, and the motor rotates in the reverse direction to return the nut assembly 46, the arm 40, the staff 18 and the signal 16 to the standby position.
  • the lamp 78 is deenergized by operation of the position responsive switch 92.
  • One important advantage of the signalling apparatus 10 is that in addition to having many advantages when used alone, it is well suited for use with a railway appliance such as a derail.
  • the apparatus 10 can easily be combined with an existing or newly installed appli- 7 ance, and important advantages reuslt from its use in combination with such an appliance.
  • the signalling apparatus of the present invention is shown installed on track including rails R and crossties C near a derail 96.
  • the combination of the apparatus 10 and the derail 96 provides an effective track safety apparatus because the signal provides a warning as well as an indication of the presence of the derail, while the derail prevents entry onto the track if the signal is ignored.
  • Both the derail 96 and the signalling apparatus 10 are operated from a remote point by a single controller (not shown) effective to control an operating mechanism 98 for the derail 96.
  • a single controller not shown
  • the details of construction of the derail 96 and the operating mechanism 98 are incidental to the present invention, and complete descriptions of these devices may be found in US. Pat. No. 2,829,246, Hayes, granted Apr. 1, 1958, and a copending application of Brice E. Hayes, Ser. No. 547,531, filed May 4, 1966, now Pat. No. 3,470,371.
  • the derail includes a derailing shoe 100 slidably mounted on a base 102 and movable between on rail and off rail positions by a reciprocal actuating element 104.
  • a pair of limit switches 106 and 108 shown only in part in FIG. 6, are operated by the operating mechanism 98 in the opposed positions of the derail. In the illustrated on rail position, normally open contacts 106a of switch 106 are closed, while normally open contacts 108a of switch 108 are open.
  • contacts 106a are opened and contacts 108a are closed.
  • the limit switches 106 and 108 may include additional contacts serving in the control of the derail operating mechanism and for providing readback indications of derail position, and the like.
  • the signalling apparatus 10 is easily connected for operation with the derail 96 so that the signal is moved to its active position when the derail is moved on rail, and is moved to its inactive position when the derail is moved off rail.
  • the signal is moved by its own operating mechanism and not by the operating mechanism of the derail, and the signal is not operated until after the derail has completed its movement. As a result, the signal cannot give a false indication of the presence or absence of the derail should the derail for some reason fail to operate.
  • the conductors 72 and 74 of the control circuit 66 are connected by way of the limit switches 106 and 108 to the power supply conductor 83, and the controller 70 for the signal is eliminated.
  • the indicator lamps 76 and 78 are connected between the conductors 80 and 82 and the power supply terminal 68.
  • the controller for the derail operating mechanism as well as readback indicators for the derail operator may be also located at the remote point in accordance with known practice.
  • the control circuit 66 for the signalling apparatus 10 is not illustrated in FIG. 6 because it may be identical to FIG. 4.
  • FIGS. 5 and 6 The operation of the arrangement of FIGS. 5 and 6 will be apparent in view of the above.
  • the limit switch 108 is operated when the movement of the derail is completed. Closure of contacts 108a serves to operate the motor 42 to lower the signal 16, whereupon the lamp 76 is energized. If the derail is moved back onto the rail, contacts 106a reclose whereupon the signal is returned to its signalling position and lamps 24 and 78 are energized. If the derail fails to complete its movement the signalling apparatus 10 does not operate.
  • a remote controlled railway signal comprising:
  • an actuating element movable to first and second positions and coupled to said signal for moving said signal between the signalling and standby positions; an operating mechanism controllable from a remote location and coupled to said actuating element;
  • an indicator at the remote location for indicating when the signal is in the signalling position
  • a first sensing means operable in response to movement of the actuating element from the second position
  • a second sensing means operable in response to movement of the signal to the signalling position
  • circuit means for energizing the indicator only in response to operation of the first and second sensing means are provided.
  • the remote controlled railway signal of claim 1 said signal including a lamp, and means for energizing said lamp in response to operation of said first sensing means independently of said second sensing means.

Description

Dec. 1, 1970 E, HAY
RAILWAY SAFETY APPARATUS Filed April 25, 1968 2 Sheets-Sheet 1 INVENTOR BR/CE E. HAYES %Mz,
Attorneys Dec. 1, 1970 Filed April 25, 1968 B- E. HAYES RAILWAY SAFETY APPARATUS 2 Sheets-Sheet 2 FIG. 6
//V VENTOR BR/CE E. HAYES Attorneys United States Patent Indiana Filed Apr. 25, 1968, Ser. No. 724,089 Int. Cl. B611 5/18, 7/10 US. Cl. 340-47 3 Claims ABSTRACT OF THE DISCLOSURE A compact housing mounted along the roadbed encloses a remote controlled operating mechanism for pivoting a blue flag signal and lamp between a horizontal standby position over the roadbed and an upstanding signalling position. Readback indications are provided at the remote location, and an indication that the signal is up is prevented untl both the operating mechanism and the signal have moved. A lamp on the signal is energized independently of signal movement. The signal may be used with a derail, in which case it is operated only in response to completion of the operation of the derail.
The present invention relates to safety apparatus for railroads and more particularly to an improved remote controlled signal, which may be a blue flag signal, and also to improved apparatus including both a signal and an appliance such as a derail.
A blue flag or blue flag signal as the term is used in the railroad industry and in the present specification and claims is a signal.used on railroad track to protect humans working on or about the track and to protect equipment on the track. A blue flag signal placed on a track is a warning that the track must not be entered and that equipment on the track must not be moved. A blue flag signal may comprise a blue flag, but a blue sign orpanel supported on a staff may be used in place of a flag, and the term blue flag applies to either type. Many railroads require personnel who repair, inspect or work about a car to protect the track with a blue flag. In addition, blue flags are often used to protect tank cars, camp cars and the like. Customarily blue flags have been placed manually by workmen or other railroad personnel. This is not only inconvenient, but also is subject to the disadvantage that the regulation requiring blue flags can be forgotten or ignored. In keeping with the modern trend toward automation and electrical control of railway signalling it has been proposed to provide remote controlled blue flag signals. Devices developed for this purpose in the past have been complex, expensive, inconvenient and in some cases dangerous.
Blue flags may be used in conjunction with an appliance such as a derailing device more securely to protect workers or equipment on the track. If a derail is placed in derailing position on the track adjacent a blue flag, the track is protected against damage caused by equipment running through the blue flag should the flag be ignored or unnoticed. In the past, manually operated derails have been used with blue flag signals. This arrangement is inconvenient, especially in locations such as classification and departure tracks, loading and unloading facilities, repair shops and the like wherein protection for workers is required at frequent intervals and the derail must be moved on and off the rail frequently.
An object of the present invention is to provide improvements in railway safety apparatus.
Another object of the invention is to provide a new and improved remote controlled signal which may be a blue flag signal although principles of the invention could be applied to signals of other types.
Another object is to provide an improved remote controlled signal which is inexpensive, convenient and safe.
Another object is to provide a signal easily installed at any desired location on existing track without modification of the track or roadbed and which does not interfere with use of the track or with visibility along the track.
A further object is to provide a blue flag signal particularly suited for use with a remote controlled appliance such as a derail.
A further object of the invention is the provision of a remote controlled signal including means for providing a readback indication of signal position only when the signal itself as well as the signal operating mechanism have assumed the selected positions.
Another object of the invention is to provide improved safety apparatus including an appliance such as a derail in conjunction with a signal such as a blue flag signal and having particular utility where frequent movements of the appliance and signal are desired.
, Another object is to provide an arrangement including an appliance and a signal for indicating the position of the appliance wherein the signal is operated only in response to completion of movement of the appliance so that the signal cannot move independently of the appliance.
In brief, the above and other objects of the invention are achieved in one embodiment of the invention by a novel signalling apparatus including an operating mechanism capable of remote control and a signal movable between positions by the operating mechanism. In accordance with a feature of the invention, the signal may be a blue flag signal and is movable between an inactive or standby position in which neither the signal nor the operating mechanism interferes with use of the track and an active or signalling position in which the signal is located above the track rails. The operating mechanism is enclosed in a low housing supported between adjacent ties and between or to the side of the rails, and the signal is carried by a support staff pivotally mounted on the housing. In the inactive position, the staff extends horizontally from the housing and lies flat on or close above the roadbed. In the signalling position, the staff is pivoted upwardly to raise the signal prominently into view.
In accordance with the invention, the signal may be operated from a remote location so that manual placement and removal is avoided. The operating mechanism includes an actuating element driven by an electric motor or the like between positions for raising and lowering the signal in response to operation of a control switch or controller. One feature of the invention resides in a novel arrangement for providing readback indications of the signal position and for preventing a false indication that the signal is in the active or signalling position. A readback indication to this effect is prevented until a limit switch is operated by the actuating element and until a position responsive switch is operated by actual movement of a signal into the signalling position.
The invention further provides a novel safety apparatus including the signalling apparatus in combination with a remote controlled appliance such as a derail. The blue flag signal used with a derail produces a highly effective and convenient means for protecting the track. When the derail is on the rail, the blue flag signal is moved to its active or signalling position thus producing a warning and an indication of the presence of the derail. In accordance with the invention, the signal is operated not by the operating mechanism for the derail, but by its own operating mechanism which is actuated only after completion of movement of the derail.
The invention and its objects and advantages may be better understood from the following detailed descrip- 3 tion wherein reference is made to the accompanying drawings in which:
FIG. 1 is a perspective view of a signalling apparatus embodying the present invention;
FIG. 2 is an enlarged, perspective view of the housing of the apparatus of FIG. 1 with the cover removed to reveal the operating mechanism;
FIG. 3 is a greatly enlarged, fragmentary, sectional view in part of the apparatus of FIG. 1 with the signal in the signalling or active position;
FIG. 4 is a schematic diagram illustrating a control circuit for the apparatus of FIG. 1;
FIG. 5 is a plan view of the apparatus of FIG. 1 used with a remote controlled railway appliance; and
FIG. 6 is a fragmentary, schematic diagram illustrating portions of a circuit for controlling the apparatus of FIG. 5.
Referring now to the drawings and first to FIGS. 14 there is illustrated a signalling apparatus designated as a whole by the reference numeral 10* and constructed in accordance with the principles of the present invention. In general, the signalling apparatus includes an operating mechanism generally designated as 12 (FIG. 2) enclosed in a housing 14, together with a signal generally designated as 16 supported on a staff 18 pivotally mounted upon the housing 14. In the arrangement of FIGS. 1-4, the operating mechanism 12 is controlled by a remote control unit generally designated as 20 and illustrated only in FIG. 4 in order to move the staff 18 and signal 16 between an inactive or standby position shown in full lines in FIG. 1 and a signalling or active position shown in broken lines in FIG. 1.
In accordance with the invention, the signal 16 may be a blue flag signal and includes a sign or panel 22 supported on the staff 18, which sign may be of a blue color and may carry a suitable legend in a contrasting color. The signal 16 also includes a lamp 24 supported in a socket 26 mounted on the end of staff 18, which lamp may also be blue in color.
A blue flag signal is customarily displayed above and between or to the side of the track rails where it is highly visible from equipment moving along the track. Arrangements have been devised in the past including an operating mechanism mounted in a large, upstanding housing located to the side of the track rails for pivoting a blue flag signal in a horizontal plane well above the grade level. Such arrangements have been bulky, expensive, and inconvenient to install since in many locations they require modification of the roadbed or the like. In addition, such arrangements may be dangerous since the signal when moving in a horizontal plane over the track can strike an unsuspecting track worker.
In order to overcome the disadvantages of known arrangements, the present invention provides a compact and simple signalling apparatus which can easily be installed in any desired location in existing track without modification thereof, which does not interfere in any way with use of the track or visibility along the track, and which is not dangerous to railroad personnel. Referring to FIG. 1 the apparatus 10 is illustrated as installed in track including running rails R and crossties C. The housing 14 is compact in shape and low in silhouette and is mounted between adjacent ties and between the track rails. It should be understood that if desired, the device could be mounted to the side of the rails. The low, compact housing in no way interferes with use of the track or with visibility along the track.
In the standby condition of the signal, the apparatus is inconspicuous and unobstructive. The signal pivots with respect to the housing in a vertical plane, and in the standby position illustrated in full lines in FIG. 1 the staff 18 extends horizontally from the housing 14 so that the staff and signal lie fiat immediately over the roadbed. In this position, the signal 16 is out of sight and provides 4 no obstruction to use of or visibility along the track. In its signalling position, the staff 18 and the signal 16 are pivoted upwardly to the position shown in broken lines in FIG. 1 wherein the panel 22 and lamp 24 are disposed well above grade level in a highly conspicuous location. Furthermore, the apparatus 10 is safe because a workman could not be in the path of movement of the signal without being aware of the signal.
Proceeding now to a more detailed description of the construction and operation of the signalling apparatus 10, the housing 14 may be fabricated of metal or the like and includes an open upper wall closed by means of a cover 28 to protect the operating mechanism 12. The housing includes a pair of side flanges 30' for attaching the housing to adjacent ties C by means of lag screws or suitable fasteners 32. The housing may be easily and quickly installed at any desired location in existing track without special preparation or modification.
Movement of the signal 16 between its active and inactive positions is accomplished by pivotal or rotational movement in a vertical plane of the staff 18 with respect to the housing 14. The end of the shaft is connected to a clamp 34 fixed on a shaft 36 extending through the wall of the housing 14 and journaled for rotation in a bearing member 38. Movement is imparted to the shaft 18 and signal 16 by means of an actuating element or arm 40 attached to the shaft 36 within the housing 14.
One important aspect of the present invention resides in the fact that the signalling apparatus 10 may conveniently be controlled from a remote point. The operating mechanism 12 enclosed within the housing 14 may be of any suitable type known to those skilled in the art. In general, the operating mechanism 12 includes an electric motor 42 for rotating a screw element 44, together with a nut assembly 46 pivotally connected to the arm 40. The electric motor 42 can be rotated in two directions whereupon a drive shaft 48 of the motor connected to the screw element 44 by means of a coupling 50 rotates the screw element to move the nut assembly 46 axially along the screw element between a pair of stop members 52 and 54. Since the nut assembly 46 is pivotally mounted to a point on the arm 40, the motor 42 and screw element 44 are mounted for pivotal movement on a mounting plate 56 by means of a pivot pin assembly 58.
The nut assembly 46 may be of any suitable construction and preferably is capable of a free wheeling operation after engagement of the nut assembly with one of the stop members 52 and 54 so that the motor shaft 48 and screw element 44 may continue to rotate. In addition, the nut assembly and screw element are preferably arranged so that they provide a reversible drive translating means so that the signal staff 18 can be manually moved between positions without declutching of the drive in the event of a power failure. The nut assembly and screw may be of the type known as the Roton, of which a further description may be obtained from US. Pat. No. 3,099,168 and other patents issued to The Anderson Company, a corporation of Indiana.
In order to aid in controlling the operating mechanism 12 a pair of limit switches 60 and 62 are mounted within the housing 14 and are operated near the ends of the range of movement of the operating mechanism. A switch operating plate 64 is attached to the arm 40 which operates the switches 60 and 62 as the nut assembly nears the stop members 52 and 54. If desired the switches may be operated shortly before engagement of the nut assembly 46 with the stop members, whereupon the momentum of the operating mechanism serves to carry the nut assembly against the stop member even though the motor 42 is deenergized.
Referring now to FIG. 4, there is illustrated a control circuit generally designated as 66 for controlling the operation of the signalling apparatus 10. The control circuit 66 of the apparatus 10 is connected by a suitable five conductor cable or the like 67 with the remote control unit 20 located any desired distance from the signalling apparatus 10. For example, the apparatus could be installed on a classification or departure track in a railroad yard, and the control unit could be located in a control tower. The control circuit 66, as well as the unit 20 are supplied with power from a pair of power supply terminals 68 and 69.
In order to control the position of the signal 16 from a remote location, the control unit 20 includes an electric switch or controller 70 movable between two positions corresponding to the standby and signalling positions of the signal 16, and connected to the control circuit 66 by two conductors 72 and 74 of the cable 67. Closure of a first set of controller contacts 70a results in movement of the signal 16 to the standby condition illustrated in FIGS. 1, 2 and 4, while closure of contacts 70b results in movement of the signal 16 to its signalling position. The unit 20 also includes a pair of indicator lamps 76 and 78 connected to the circuit 66 by cable conductors 80 and 82 for indicating to the operator the position of the signal. The remaining cable conductor 83 is a power supply cable connected to the power supply terminal 69.
Movement of the signal 16 in both directions is accomplished by bidirectional or reversible operation of the motor 42. The motor includes an armature winding 84 as well as a field Winding 86, these being illustrated in FIG. 4. A pair of motor control relays 88 and 90 serve, in combination with the limit switches 60 and 62, to control both the energization and direction of operation of the motor.
In the illustrated condition of the circuit 66, the signal is at rest in the inactive or standby position shown in FIGS. 1 and 2, and the motor 42 is disconnected by the relays 88 and 90. The limit switch 60, which comprises a double pole, double throw switch, is operated by the actuating element or arm 40 and plate 64 to open a pair of sets of normally closed contacts 601; and 60b, and to close a normally open set of contacts 60c. The indicator lamp 76 is energized by a circuit including conductor 83, conductor 80, and contacts 600 of the limit switch 60 in order to provide an indication at the remote location that the signal is in the standby condition.
In order to produce a warning on the track, the operator located at the remote point can move the signal to its active or signalling position by operation of controller 70 to its alternate position to open contacts 70a and close contacts 70b. As a result, the motor 42 is operated to raise the signal, the signal lamp 24 is energized, the indicator lamp 76 is extinguished and, providing the signal operates properly, the indicator lamp 78 is energized to provide an indication that the apparatus has obtained its active or signalling position.
More specifically, closure of contacts 70b completes a circuit for energization of the motor control relay 88, this circuit including conductor 83, contacts 70b, conductor 74, and a normally closed set of contacts 62a of the limit switch 62. When the relay 88 is energized, a normally closed set of relay contacts 88a are opened and a normally open set of contacts 88b are closed. Consequently, the motor armature 84 is connected in series with the field winding 86 across the power supply terminals 68 and 69. The reversible motor 42 is designed in known manner so that it rotates in a direction for moving the nut assembly 46 along the screw member 44 away from the stop member 52 and limit switch 60. Release of the limit switch 60 results in closing of contacts 6011, thereby conditioning the circuit 66 for return of the signal 16 when the controller 70 is returned to its illustrated position, and also in opening of contacts 600 in order to open the circuit for energization of the indicator lamp 76.
Railroad signals are often subject to heavy usage and wear and also to climate extremes. Thus it may happen that the signalling apparatus 10' malfunctions and may not respond properly when the controller 70 is shifted to close contacts 70b. For example, the actuating element 40 within the housing 14 may not move all the way to its alternate position. Even if the element 40 completes its movement the staff 18 and signal 16- may not be raised due to loosening of the clamp 34, a large snow load on the panel 22, or the like. Since blue flag signals are commonly used at locations which are critical from a safety standpoint, it is important that the operator at the remote location be advised in the event of any malfunction.
An important feature of the invention resides in the provision of a novel arrangement for assuring that the signal lamp 24 is energized even if the signal 16 is not fully raised, and also for preventing a readback indication indicating satisfactory operation of the apparatus unless the signal 16 is actually moved to the active position.
More specifically, when the operating mechanism 12 begins its movement, the plate 64 releases the limit switch 60 to close the normally closed set of contacts 60b, and complete a circuit for energization of the signal lamp 24 across the power supply terminals 68 and 69. The signal lamp 24 is accordingly energized shortly after operation of the controller 70 to provide a danger indication independently of whether or not the signal 16 is moved all the Way to its signalling position, so that at least a partial signal is provided.
In order to prevent a readback indication if the signal 16 is not fully raised, the circuit for energizing the indicator lamp 78 includes a position responsive switch 92 in series with the contacts 60b of the limit switch 60. As shown in FIG. 3, the switch 92 may comprise a mercury contact switch mounted within the lamp housing 26 by means of a bracket 94, although other types of switch could be used. The switch 92 is closed only in response to movement of the housing 26, and thus of the signal 16, to the upright signalling or active position, and a false readback indication is prevented. This is an improvement over prior art arrangements wherein operation of a limit switch by the operating mechanism provides a readback regardless of the actual signal position. When the limit switch 60 is released and when the position responsive switch 92 is operated, a circuit including contacts 60b, switch 92, conductor 82 and conductor 83 energizes the indicator lamp 78.
When the actuating element 40 reaches the end of its range of movement, plate 64 operates the limit switch 62. Accordingly, the contacts 62a are opened to deenergize the relay 88 to deenergize the motor 42. The signal apparatus remains at rest in its active or signalling condition until such time as the remote control unit 20 is operated to return the signal to its inactive position.
Operation of the signalling apparatus 10 in the reverse direction is also accomplished by movement of the controller 70. Closure of contacts 70a completes a circuit for energization of the motor control relay through conductor 72 and contacts 60a of the limit switch 60. A normally closed set of relay contacts 90a are opened and contacts 90b are closed, and the armature 84 and field Winding 86 of the motor 42 are connected in series across the power supply. The polarity of the field winding 86 is reversed by operation of the relay 90 rather than the relay 88, and the motor rotates in the reverse direction to return the nut assembly 46, the arm 40, the staff 18 and the signal 16 to the standby position. During this movement, the lamp 78 is deenergized by operation of the position responsive switch 92. When the plate 64 operates the limit switch 60 to open contacts 60a, the motor is deenergized by deenergization of the relay 90, and the lamp 24 is deenergized by opening of contacts 60b. Closure of contacts 600 completes the above described circuit for energization of the indicator lamp 7 6'.
One important advantage of the signalling apparatus 10 is that in addition to having many advantages when used alone, it is well suited for use with a railway appliance such as a derail. The apparatus 10 can easily be combined with an existing or newly installed appli- 7 ance, and important advantages reuslt from its use in combination with such an appliance.
Having reference to FIGS. and 6, the signalling apparatus of the present invention is shown installed on track including rails R and crossties C near a derail 96. The combination of the apparatus 10 and the derail 96 provides an effective track safety apparatus because the signal provides a warning as well as an indication of the presence of the derail, while the derail prevents entry onto the track if the signal is ignored.
Both the derail 96 and the signalling apparatus 10 are operated from a remote point by a single controller (not shown) effective to control an operating mechanism 98 for the derail 96. The details of construction of the derail 96 and the operating mechanism 98 are incidental to the present invention, and complete descriptions of these devices may be found in US. Pat. No. 2,829,246, Hayes, granted Apr. 1, 1958, and a copending application of Brice E. Hayes, Ser. No. 547,531, filed May 4, 1966, now Pat. No. 3,470,371.
As described in the above patent and application, the derail includes a derailing shoe 100 slidably mounted on a base 102 and movable between on rail and off rail positions by a reciprocal actuating element 104. A pair of limit switches 106 and 108, shown only in part in FIG. 6, are operated by the operating mechanism 98 in the opposed positions of the derail. In the illustrated on rail position, normally open contacts 106a of switch 106 are closed, while normally open contacts 108a of switch 108 are open. When the operating mechanism 98 and derail 96 are moved to their alternate positions in which derail '96 is moved off the rail, contacts 106a are opened and contacts 108a are closed. It should be understood that the limit switches 106 and 108 may include additional contacts serving in the control of the derail operating mechanism and for providing readback indications of derail position, and the like.
The signalling apparatus 10 is easily connected for operation with the derail 96 so that the signal is moved to its active position when the derail is moved on rail, and is moved to its inactive position when the derail is moved off rail. In accordance with an important feature of the invention, the signal is moved by its own operating mechanism and not by the operating mechanism of the derail, and the signal is not operated until after the derail has completed its movement. As a result, the signal cannot give a false indication of the presence or absence of the derail should the derail for some reason fail to operate.
In order to control the signalling apparatus 10 in accordance with the actual position of the derail, the conductors 72 and 74 of the control circuit 66 are connected by way of the limit switches 106 and 108 to the power supply conductor 83, and the controller 70 for the signal is eliminated. In order to provide readback indications at a remote point, the indicator lamps 76 and 78 are connected between the conductors 80 and 82 and the power supply terminal 68. The controller for the derail operating mechanism as well as readback indicators for the derail operator (not shown), may be also located at the remote point in accordance with known practice. The control circuit 66 for the signalling apparatus 10 is not illustrated in FIG. 6 because it may be identical to FIG. 4.
The operation of the arrangement of FIGS. 5 and 6 will be apparent in view of the above. When the derail is moved from its illustrated position as by operation of a remote controller, the limit switch 108 is operated when the movement of the derail is completed. Closure of contacts 108a serves to operate the motor 42 to lower the signal 16, whereupon the lamp 76 is energized. If the derail is moved back onto the rail, contacts 106a reclose whereupon the signal is returned to its signalling position and lamps 24 and 78 are energized. If the derail fails to complete its movement the signalling apparatus 10 does not operate.
While the present invention has been described in connection with details of certain embodiments, many other modifications and embodiments may be devised by those skilled in the art. The invention is not limited to such details except as set forth in the following claims.
What is claimed and desired to be secured by Letters Patent of the United States is:
1. A remote controlled railway signal comprising:
a signal mounted for movement between signalling and standby positions;
an actuating element movable to first and second positions and coupled to said signal for moving said signal between the signalling and standby positions; an operating mechanism controllable from a remote location and coupled to said actuating element;
an indicator at the remote location for indicating when the signal is in the signalling position;
a first sensing means operable in response to movement of the actuating element from the second position;
a second sensing means operable in response to movement of the signal to the signalling position;
and circuit means for energizing the indicator only in response to operation of the first and second sensing means.
2. The remote controlled railway signal of claim 1, said second sensing means comprising a position responsive switch mounted on said signal.
3. The remote controlled railway signal of claim 1, said signal including a lamp, and means for energizing said lamp in response to operation of said first sensing means independently of said second sensing means.
References Cited UNITED STATES PATENTS 269,955 1/ 1883 Paullin 246477 627,243 6/1899 Taylor 246242 X 1,142,807 6/1915 Ferguson 246477 X 1,604,014 lO/1926 Billups 34047 UX 1,714,074 5/1929 Burch et al. 34047 2,420,066 5/1947 Conway 340226 2,473,187 6/1949 Zelk 340-127 3,085,238 4/1963 Lewis 340-5O 3,128,448 4/1964 Shumcr, et al 340122 X 3,228,019 1/ 1966 Visceglia 340282 X FOREIGN PATENTS 1,563 1896 Great Britain.
THOMAS B. HABECKER, Primary Examiner K. N. LEIMER, Assistant Examiner US. 01. X.R.
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US3848244A (en) * 1972-07-10 1974-11-12 J Goodwin Water skier{40 s safety device
US5305975A (en) * 1992-11-06 1994-04-26 Douglass Charles L Flagging apparatus and method
US5791605A (en) * 1997-02-11 1998-08-11 Howie, Ii; Thomas D. Railroad signaling method and apparatus
US6435459B1 (en) * 1999-10-28 2002-08-20 Dialight Corporation LED wayside signal for a railway
GB2403053B (en) * 2003-06-18 2006-11-29 Discovery Partnership Uk Ltd Remotely controlled device/equipment for the marking of railway line sections temporarily taken out of use
GB2431034A (en) * 2005-10-06 2007-04-11 Multiclip Co Ltd Track circuit apparatus for taking possession of a section of track by altering the circuit as an indication of an intention to take possession
US20070146152A1 (en) * 2005-12-23 2007-06-28 Welles Kenneth B Monitoring status of railyard equipment using wireless sensing devices
US20080302921A1 (en) * 2007-06-08 2008-12-11 Schalk David A Railroad Switch Indicator
US20110198448A1 (en) * 2010-02-15 2011-08-18 Allement Mark T Linkage assembly for operatively connecting a blue flag to a derail
US8529107B2 (en) 2010-04-21 2013-09-10 Tripsplusone, Inc. System for use in illumination of railway feature
US8695928B1 (en) 2009-07-24 2014-04-15 David A. Schalk Railroad switch indicator with distance amplifier
NL2013458B1 (en) * 2014-09-11 2016-09-28 Nedflex Holding B V Tramline security device.
FR3070953A1 (en) * 2017-09-13 2019-03-15 4Nrj LIGHTING DEVICE FOR RAILWAYS
US10427698B2 (en) 2016-01-29 2019-10-01 Green Timber Energy Train derailer placement warning device
US11400963B2 (en) * 2018-09-05 2022-08-02 Focused Technology Solutions, Inc. Derail warning light system
US11919553B1 (en) * 2019-10-10 2024-03-05 David A. Schalk Railroad switch position indicator

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US3848244A (en) * 1972-07-10 1974-11-12 J Goodwin Water skier{40 s safety device
US5305975A (en) * 1992-11-06 1994-04-26 Douglass Charles L Flagging apparatus and method
US5791605A (en) * 1997-02-11 1998-08-11 Howie, Ii; Thomas D. Railroad signaling method and apparatus
US6435459B1 (en) * 1999-10-28 2002-08-20 Dialight Corporation LED wayside signal for a railway
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US7388483B2 (en) * 2005-12-23 2008-06-17 General Electric Company Monitoring status of railyard equipment using wireless sensing devices
US20080302921A1 (en) * 2007-06-08 2008-12-11 Schalk David A Railroad Switch Indicator
US7735784B2 (en) * 2007-06-08 2010-06-15 Schalk David A Railroad switch indicator
US8695928B1 (en) 2009-07-24 2014-04-15 David A. Schalk Railroad switch indicator with distance amplifier
US20110198448A1 (en) * 2010-02-15 2011-08-18 Allement Mark T Linkage assembly for operatively connecting a blue flag to a derail
US8529107B2 (en) 2010-04-21 2013-09-10 Tripsplusone, Inc. System for use in illumination of railway feature
NL2013458B1 (en) * 2014-09-11 2016-09-28 Nedflex Holding B V Tramline security device.
US10427698B2 (en) 2016-01-29 2019-10-01 Green Timber Energy Train derailer placement warning device
FR3070953A1 (en) * 2017-09-13 2019-03-15 4Nrj LIGHTING DEVICE FOR RAILWAYS
US11400963B2 (en) * 2018-09-05 2022-08-02 Focused Technology Solutions, Inc. Derail warning light system
US20230150558A1 (en) * 2018-09-05 2023-05-18 Railserve, Inc. Derail Warning Light System
US11919553B1 (en) * 2019-10-10 2024-03-05 David A. Schalk Railroad switch position indicator

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