Railroads are generally constructed of a pair of elongated, substantially parallel rails, which are coupled to a plurality of laterally extending ties via metal tie plates and spikes and/or spring clip fasteners. After construction railroads may require regular maintenance. When maintaining a railroad, track workers often need to work around and between the rails. Thus, it is important to have robust roadway worker protection systems to promote worker safety. For example, a shunt device may be mounted on two running rails of a work zone to form a close circuit between the two rails. If properly installed, the shunt device may indicate the close-circuit status to an operations control center (OCC). The OCC may detect the shunt device by treating it as a train, which also creates a short circuit between two rails. Thus, the shunt device may prevent railcars or locomotives from entering an occupied work area.
Existing shunt devices may be secured onto two running rails by clamp-type devices. However, a shunt device may not always be operational after its installation. For example, a shunt device may not be correctly clamped onto the rails, or an onsite worker may trip on a wire on the shunt device and disconnect it from the rails. Despite the possibility of a faulty connection or other error, onsite workers often assume that a shunt device would be operational once installed. In existing shunt devices, there may be no alert or warning if a shunt device is removed without authorization, which creates a potential safety hazard to onsite workers. Accordingly, it is desirable to improve functions of rail-mounted shunt devices for increased safety.
The present disclosure generally relates to providing multi-fold protection for track workers using a rail-mounted shunt device (sometimes called shunting device). According to some aspects of the present disclosure, a shunt device may be magnetically coupled to both running rails via two magnetic end components. A shunt device may have a central unit connected to end components via two electrical wires. On-board circuitry may be implemented in the central unit for various functions such as transmitting and receiving signals and indicating whether the shunting device is operational. When properly installed, a shunt device may send signals to an operations control center (OCC) to indicate a presence of the shunt device, and the OCC may display a track occupancy light (TOL) to indicate that the track section is occupied. Accordingly, a shunt device disclosed herein may prevent rail vehicles from entering occupied work area(s). The purpose is to provide a safe procedure for track access in order to perform track maintenance or repair in fixed or moving work zones during revenue hours or with test trains or maintenance vehicles operating during repair.
The present disclosure teaches shunt devices that have self-diagnosis capabilities, making them “failsafe.” For example, a failsafe shunt device may be equipped with visual and/or audio alarms that issue warnings to surrounding rail workers when the shunt device stops being properly connected to both rails or when a rail vehicle is approaching. Shunt devices disclosed herein may work seamlessly with positive train control (PTC) technologies. For example, a shunt device may communicate with a control center either directly or indirectly through wayside communications systems. Related methods for using the disclosed shunt devices are also described.
Reference is now made to the following descriptions taken in conjunction with the accompanying drawings.
Various embodiments of a failsafe rail-mounted shunt device and associated procedures and methods of using such shunt device according to the present disclosure are described. It is to be understood, however, that the following explanation is merely exemplary in describing the devices and methods of the present disclosure. Accordingly, several modifications, changes and substitutions are contemplated.
At least one of the end components 112 and 114 may be implemented a magnet, which may be made of any suitable magnetic, conductive material. In an embodiment, the failsafe shunt device 110 may attach magnetically to the web of both running rails 102 and 104 via the end components 112 and 114. The magnets may take any suitable shape as well. For example, as shown in
Electrical wires 116 and 118 may provide electrical connection between the end components and the central unit 120. Upon proper magnetic coupling, the failsafe shunt device 110 may form an electrical connection between the rails 102 and 104 (similar to a short circuit), which creates the “shunting.”
The central unit 120 may comprise an electronic board, where on-board circuitry may be implemented for various functions. For example, on-board circuitry may indicate whether the shunting device 110 is correctly installed and operational. In an embodiment, the operational status may be indicated by a green light (or any other signaling mechanism) on the central unit 120. The central unit 120 may comprise one or more transceivers (transmitter and/or receiver) for communication with other devices such as an operations control center (OCC), a rail vehicle, or a wayside communications system. The central unit 120 may comprise other components such as a switch to turn on/off the shunt device 110, a rotary dial to change communication mode, and so forth.
In practice, after the failsafe shunt device 110 is properly installed in the work zone 106, the failsafe shunt device 110 may send one or more signals 130 to an OCC (not pictured). A signal 130 may take any suitable data format, and may be sent continuously, or periodically, or only upon installation and removal of the failsafe shunt device 110. An operations control center may be located remotely from the work zone 106, and may be implemented as any rail control center that can communicate with the failsafe shunt device 110 and other rail vehicles. Upon receiving the signals 130 from the failsafe shunt device 110, an OCC may indicate the presence of the shunt device 110 on a screen 132. For example, the failsafe shunt device 110 may be displayed on the screen 132 as a track occupancy light (TOL). In some embodiments, the presence is indicated such that the failsafe shunt device 110 can be distinguished from a rail vehicle.
Rail vehicles such as railcars or locomotives are often equipped with Automatic Train Protection (ATP) systems that communicate with an OCC. Therefore, the failsafe shunt device 110 prevents operators of railcars or locomotives from obtaining proper authorization to enter corresponding work area(s). Suppose, for example, a rail vehicle 108 (e.g., a train, locomotive, or railcar, etc.) is traveling along the rails 102 and 104 and approaching the failsafe shunt device 110. According to some aspects of the present disclosure, the rail vehicle 108 may be stopped from entering the work zone 106, because an OCC would notify in advance the rail vehicle 108 of the presence of the failsafe shunt device 110. For example, a rail employee at the OCC may stop routing trains or other vehicles into the work zone 106. Consequently, train operators may not get proper wayside indication (e.g., green lights) to enter the work zone 106, where the failsafe shunt device 110 resides. Additionally or alternatively, the failsafe shunt device 110 may communicate directly with the oncoming rail vehicle 108 (e.g., at certain distances) to warn the latter of its presence. Visual and/or audio alarming components on the central unit 120 may also be picked up by the rail vehicle 108. Such features may provide an extra layer of safety.
Positive train control (PTC) is a system of functional requirements, currently under development, for monitoring and controlling train movements in order to provide increased safety. In an embodiment, the failsafe shunt device 110 may work seamlessly with PTC technologies in its communications with rail vehicles and/or with a control center (e.g., OCC). For example, the failsafe shunt device 110 may have transceivers that work near (at and/or close to) various frequencies such as 430 MHz, 220 MHz, 900 MHz, 2.4 GHz, 2.4 MHz, global positioning system (GPS) frequencies, and cellular frequencies. The 220 MHz is a Federal Communications Commission (FCC)-approved frequency band for PTC communications. The shunt device 110 may communicate with a control center directly through GPS communication links or cellular communication links. Since the failsafe shunt device 110 is electrically connected to both rails, the failsafe shunt device 110 may also send a signal to a control center via the running rails (e.g., at 35 volts DC).
In geographical areas where there is no wireless signal (sometimes referred to as dark territories), the failsafe shunt device 110 may communicate with a control center indirectly through wayside communications systems such as a signaling tower or a bungalow. Such wayside communications systems may be deployed along a railroad to serve as an intermediary communications link. For example, a wayside communications system may receive signals 130 from the failsafe shunt device 110 via the rails or wirelessly. In turn, the wayside communications system may relay the signals 130 to a control center (directly or through other relay systems) to indicate the presence of the shunt device 110.
According to some aspects of the present disclosure, the failsafe shunt device 110 may communicate with rail vehicles (e.g., wirelessly around a 400 MHz radio link, or via the running rails). For example, when the rail vehicle 108 is approaching the work zone 106, the failsafe shunt device 110 may start to issue alarms at pre-determined distances. The rail vehicle 108 may communicate in turn with a control center to confirm how far the train is from the work zone 106. If the rail vehicle 108 gets too close, mandatory braking may be enforced to prevent potential danger to onsite workers.
The failsafe shunt device 110 may be a proactive shunt strap equipped with a self-diagnosis system. For example, the failsafe shunt device 110 may be equipped with visual and/or audio alarms that can be recognized by surrounding devices and workers. In an embodiment, when someone disconnects the failsafe shunt device 110 without proper authorization (e.g., accidentally, intentionally, or inadvertently), the visual and/or audio alarms may be triggered. For example, there may be a flashing light and a loud alarm on the central unit 120. The warning messages may be picked up by surrounding personnel.
Members of the onsite work crew, such as worker 140, may be equipped with personal alert devices 142 that communicate wirelessly with the failsafe shunt device 110. The personal alert devices may be carried as armband or on-head devices. For example, the worker 140 has an armband device 142 as his personal alert device. The failsafe shunt device 110 may send out a secure radio frequency (RF) signal to wayside and/or personal devices within the output area, which may pick up the warning from the failsafe shunt device 110 in case of an unauthorized disconnection or an oncoming train. Thus, the failsafe shunt device 110 warns workers of the potential danger which the workers might not otherwise notice due to their concentration on their work and the high volume of noise. Features disclosed herein make the shunt devices “failsafe.”
One of the issues with existing clamp-type shunting devices is that, from the perspective of a control center, a clamp-type shunting device may not be distinguishable from a rail vehicle such as a train. The present disclosure may implement shunting delay, e.g., by having on-board circuitry on the central unit 120 to alternatively switch the rail connection on (shunt) and off (no shunt). This signaling mechanism creates a blinking effect at the control center to indicate that the signal is arriving from a shunting device, not a rail vehicle. That is, the failsafe shunt device 110 may send a signal to a control center (or to another device) to specify the identity of the failsafe shunt device 110.
Although not depicted, the central unit 120 may further comprise a computer or data processing system that includes a processor configured to execute software program(s) stored in a memory for the purposes of performing one or more of the procedures and methods disclosed herein. A processor on the central unit 120 may be coupled to a communication interface to receive and to transmit data. For example, there may be a communication interface between the central unit 120 and another device (e.g., the rail vehicle 108) for Interoperable Electronic Train Management System (I-ETMS) PTC, engineer display, event recording, and/or other functions. Data communication may occur over interface via wired Ethernet or via wireless channels at 2.4 MHz or 900 MHz. The rail vehicle 108 may provide ranging within one meter as well as a long distance up to two miles. The rail vehicle 108 may provide ID recognition of a moving or fixed asset. There is a redundancy of warning mechanisms to provide enhanced safety. There may be a direct link from the rail vehicle 108 to a track inspector, work gangs, and hy-rail.
To work with embodiments of failsafe shunt devices disclosed herein, rail personnel including onsite workers and supervisors at an operations control center may adapt procedural changes. Work zone personnel responsibilities may include using rail-mounted failsafe shunt devices (sometimes referred to as shunt straps) as well as wearing portable warning horn and lights, and/or personal alert device(s) in work blocks for all types of track work. The procedural changes may provide a safer procedure for track access in order to perform track maintenance or repair in fixed or moving work zones during revenue hours or with test trains operating during repair.
According to some aspects of the present disclosure, a shift supervisor may authorize and assemble work maintenance crew to perform track work. The supervisor may select a qualified person of the work crew as the designated work crew coordinator to manage activities with the OCC and to provide on-track safety for all members of the work crew. Only a designated qualified person may request and initiate a track work area and should comply with safety procedures, policies, and standards in order to ensure optimum safety to all personnel.
According to some aspects of the present disclosure, work crew coordinator responsibilities may include the following:
According to some aspects of the present disclosure, each individual crew member is responsible for following all on-track safety rules. All crew members will be required to adhere to all agency safety guidelines and personal protective equipment (PPE) requirements.
According to some aspects of the present disclosure, OCC employee responsibilities may include the following:
According to some aspects of the present disclosure, shift supervisor responsibilities may include the following:
In terms of Work Crew Parameters, According to some aspects of the present disclosure, a maintenance crew will consist of a minimum of two employees except when supporting contractors or other departments. All crew members will adhere to all agency safety guidelines and PPE requirements. Crew members shall not be permitted in the work block until given permission by the designated qualified person. All crew members will establish and maintain voice communication with designated flagger(s)/watchperson(s)/lookout(s). All crew members shall adhere to all designated safety personnel and warning devices and leave the fouling space when required.
In terms of OCC Parameters, according to some aspects of the present disclosure, operations may not allow reverse traffic for any reason until the following conditions are met: (1) the work crew is notified; and (2) it is verified that all safety and warning equipment is in place as per agency procedures and guidelines. Prior to reversing traffic, OCC may ask the designated qualified person, “Are failsafe rail mounted portable shunt straps, portable warning horn and lights, and/or personal alert device turned on?” in order to confirm that all magnetically attached shunt straps are turned on and functioning properly. OCC must verify a “TOL”.
The present disclosure describes a safe procedure for installing failsafe shunt straps isolating a section of track that will ensure safe working conditions for track workers from revenue trains, test trains, and potential human error.
According to some aspects of the present disclosure, the installation of failsafe shunt devices may follow certain procedures. For example, shunt straps may be used when a work area does not have a shunting vehicle, or when the shunting vehicle is moving throughout the work block. After confirming a work order, a designated qualified person shall install the required shunt strap. The shunt strap may be installed in the first track circuit, both ends, inside the approved work block area. Prior to installing the shunt strap, the designated qualified person will establish contact with OCC and request track access by the following procedure:
1. Give radio number.
2. Report number of works in a work crew.
3. State the location of the work area.
4. State nature of work and/or repairs; give estimated work time.
5. If necessary, request a speed restriction.
According to some aspects of the present disclosure, removal of the failsafe shunt devices may follow certain procedures. Prior to removing the shunt strap, the designated qualified person will establish contact with OCC and request track access and permission to remove shunt straps. Once OCC grants permission, the designated qualified person shall remove the shunt strap and thereafter verify with OCC that the TOL is off and that the area is not shown as occupied.
At action 420, a shunt device (e.g., the failsafe shunt device 110) may be magnetically coupled to two rails of a railroad. At action 430, one or more signals may be transmitted from a shunt device to an OCC to indicate a presence of the shunt device. An identity of the shunt device may be specified to distinguish the device from rail vehicles (e.g., showing the shunt device as a blinking symbol at the OCC instead of a constant symbol). At action 440, a shunt device may indicate an operational status of the shunt device using a signaling mechanism (e.g., a green light) located thereon.
At action 450, a rail employee located at the OCC may verify that the shunt device is operational, and the verification may be based on a TOL displayed at the OCC. Upon verification, at action 460 the rail employee at the OCC may grant access to a work crew to enter a work zone and start working. At action 470, a shunt device may issue warnings to surrounding rail workers when the shunt device stops being properly connected to both rails. The shunt device may also issue warnings when there is an oncoming rail vehicle.
After onsite work is completed, at action 480, a designated work crew coordinator may contact the OCC to request permission to remove the shunt device. At action 482, the designated work crew coordinator may remove the shunt device based upon receiving permission from the OCC. After removal of the shunt device, at action 484 the designated work crew coordinator may verify with the OCC that a TOL corresponding to the shunt device is off (i.e., the work zone is now clear).
While various embodiments of rail-mounted shunt devices and related methods of using such devices have been described above, it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. Moreover, the above advantages and features are provided in described embodiments, but shall not limit the application of the claims to processes and structures accomplishing any or all of the above advantages.
Additionally, the section headings herein are provided for consistency with the suggestions under 37 CFR 1.77 or otherwise to provide organizational cues. These headings shall not limit or characterize the invention(s) set out in any claims that may issue from this disclosure. Specifically and by way of example, the description of a technology in the “Background” is not to be construed as an admission that technology is prior art to any invention(s) in this disclosure. Neither is the “Brief Summary” to be considered as a characterization of the invention(s) set forth in the claims found herein. Multiple inventions may be set forth according to the limitations of the multiple claims associated with this disclosure, and the claims accordingly define the invention(s), and their equivalents, that are protected thereby. In all instances, the scope of the claims shall be considered on their own merits in light of the specification, but should not be constrained by the headings set forth herein.
This application claims priority to U.S. Provisional Application No. 62/071,816, filed Oct. 3, 2014 and entitled “Failsafe Rail Mounted Shunt Device,” and to U.S. Provisional Application No. 62/215,858, filed Sep. 9, 2015 and entitled “Failsafe Rail Mounted Shunt Device,” both of which are hereby incorporated by reference in their entirety.
Number | Date | Country | |
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62071816 | Oct 2014 | US | |
62215858 | Sep 2015 | US |