FIELD OF INVENTION

This invention relates to visual indicator devices, for use in visually indicating the presence of an overhead conductor. The invention also extends to a system for monitoring a condition of visual indicator devices. The invention also extends to a method of monitoring at least one condition of the visual indicator devices.

BACKGROUND OF INVENTION

Electrical locomotives are powered from a substation through overhead traction lines. This may be by the use of an electrical conductor in the form of a pantograph. These overhead traction lines are at a set height that varies according to the rail gauge. In general, overhead railway traction lines are visible in good lighting weather condition. However, the visibility is drastically reduced in poor lighting conditions.

To effectively conduct electricity, a consistent nominal force is required to be maintained between the pantograph and overhead line. The overhead wires are tensioned with forces that resist the uplift force of the pantograph. These uplift forces are generated by the locomotive pantograph. Unavailability of the overhead track equipment leads to the pantograph raising above the set rail maximum height. This results in a phenomenon known as a hook-up.

In a hook-up, the pantograph will rip off the entire overhead track equipment including but not limited to contact wires, droppers, Catenary or Tiger Wire, Steady Arms, Insulators, Push-Pull Pipe, and the locomotive roof equipment (insulator, busbars). Due to the abovementioned failure, the overhead line has to be closed and rendered out of commission until repairs can be done. For the repairs to commence, the train involved in the hook-up must be hauled out of the dead section using another set of locomotives from the nearest depot, which is a lengthy exercise and time consuming.

The inventors realized that a hook-up incident must be avoided. One of the highest contributing factors to hook-up incident is a train driving into a section where the overhead contact wire has been stolen with all the pantographs from the train being configured in the raised position.

The present invention addresses at least some of these drawbacks.

SUMMARY OF INVENTION

According to a first aspect of the invention there is provided a visual indicator device for an overhead conductor, the visual indicator device including: a housing; a light reflector element fitted to the housing for reflecting light away from the housing; and a securing arrangement extending from the housing for fixedly securing the housing relative to the overhead conductor.

The securing arrangement may include securing gripping formations for securingly gripping to the overhead conductor to secure the visual indicator device relative to the overhead conductor.

The securing arrangement may further include: an elongate, open ended cylindrical member defining an axis; a first side cover defining a first opening that is arranged to be co-axial with the axis of the cylindrical member, and defining a second opening that is spaced from the first opening; a second side cover comprising a locating element for snugly fitting through the cylindrical member and the first opening, so as to locate the first side cover relative to the second side cover, the second side cover comprising a receiving element that is spaced from the locating element; and a securing element for fitting though the second opening and receiving element to secure the first side cover relative to the second side cover and thereby fix the position of the securing gripping formations relative to each other. Each end of the first and second covers may include the gripping formations which may be shaped and sized to be snugly accommodated in a recess defined in the overhead conductor, and may be arranged to move towards each other when the securing element is received by the receiving element.

The visual indicator device may include a condition monitoring system that is accommodated in the housing for continuously monitoring at least one condition of the visual indicator device.

The condition monitoring system may include: a communication module for communicating, in near real-time, with a satellite to receive a positioning signal of the visual indicator device; a processor and a memory device coupled to the processor, the memory device containing instructions which, when executed can cause the processor to: receive the position signal of the visual indicator device from the communication module; determine whether the received position signal corresponds to a reference position signal of the visual indicator device which corresponds to a predefined reference location of the visual indicator device that is secured to the overhead contact wire; and generate a signal when the received position signal of the visual indicator device does not correspond with the reference position signal of the visual indicator device.

The condition monitoring system may further include a detection element comprising a sensor, which is arranged to sense a condition associated with the visual indicator device, wherein the condition may for example be the impact pressure applied to the visual indicator device; and wherein the processor is arranged to: collect the sensed condition of the visual indicator device; determine whether the sensed condition corresponds with a predefined, reference condition; and generate a signal when the sensed condition does not correspond with the predefined, reference condition.

The condition monitoring system may include an accelerometer device which is arranged to measure, in near real-time, an acceleration condition of the visual indicator device; and wherein the processor is arranged to: collect the measured acceleration condition of the visual indicator device; determine whether the measured acceleration condition corresponds with a predefined, reference acceleration condition of the visual indicator device; and generate a signal when the measured acceleration condition of the visual indicator device does not correspond with the predefined, reference acceleration condition of the visual indicator device.

According to a second aspect of the invention, there is provided an overhead conductor assembly comprising: an overhead conductor; and a visual indicator device as hereinbefore described secured to the overhead conductor.

According to a third aspect of the invention, there is provided a visual indicator device condition monitoring system comprising: a processor and a memory device coupled to the processor, the memory device containing instructions which, when executed by the processor is arranged to: receive, in near real-time, a condition of the visual indicator device; determine whether the received condition corresponds to a reference condition of the visual indicator device that is secured to a predefined section of an overhead conductor; and generate a signal when the received condition of the visual indicator device does not correspond with the reference condition of the visual indicator device.

According to a fourth aspect of the invention, there is provided a computer- implemented method of monitoring a condition of visual indicator device, the method comprising: receiving, in near real-time, a condition of the visual indicator device; determining whether the received condition corresponds to a reference condition of the visual indicator device that is secured to a predefined section of an overhead conductor; and generating a signal when the received condition of the visual indicator device does not correspond with the reference condition of the visual indicator device.

BRIEF DESCRIPTION OF DRAWINGS

The objects and features of the present invention will become fully apparent from following the description taken in conjunction with the accompanying drawings. Undertaking that these drawings depict only typical embodiments of the invention and are therefore, not to be considered limiting its scope, the invention will be described and explained with additional specific and detail through the use of the accompanying drawings in which:

In the drawings:

Figure 1 shows an exploded view diagram of a visual indicator device in accordance with the invention;

Figure 2 shows an assembled perspective view of the visual indicator device;

Figure 3 shows the visual indicator device of Figure 2 secured on an overhead contact wire; and

Figure 4 shows a network comprising a system and a server for monitoring a condition of the visual indicator device of Figures 1 to 3.

DETAILED DESCRIPTION OF AN EXAMPLE EMBODIMENT

While various inventive aspects, concepts and features of the invention may be described and illustrated herein as embodied in combination in the exemplary embodiments, these various aspects, concepts and features may be used in many alternative embodiments, either individually or in various combinations and sub combinations thereof. Unless expressly exclude herein all such combinations and sub combinations are intended to be within the scope of the present invention. Still further, while various alternative embodiments as to the various aspects, concepts and features of the invention - such alternative structures, configurations, methods, devices and components, alternatives as to form, fit and function, and so on may be described herein, such descriptions are not intended to be a complete or exhaustive list of available alternative embodiments, whether presently known or later developed.

Those skilled in the art may readily adopt one or more of the inventive aspects, concepts or features into additional embodiments and uses within the scope of the present invention even if such embodiments are not expressly disclosed herein. Still further, exemplary or representative values and ranges may be included to assist in understanding the present disclosure; however, such values and ranges are not to be construed in a limiting sense and are intended to be critical values or ranges only if so expressly, stated. Moreover, while various aspects, features and concepts may be expressly identified herein as being inventive or forming part of an invention, such identification is not intended to be exclusive but rather there may be inventive aspects, concepts and features that are fully described herein without being expressly identified as such or as part of a specific invention.

As can be seen in Figures 1 to 3 of the drawings, there is provided a visual indicator device for an overhead power line or conductor, the visual indicator device being designated reference numeral 10. The visual indicator device 10 comprises an elongate housing 12 that is substantially cuboid. The elongate 12 housing has a front, inwardly recessed face 14 and a rear, inwardly recessed face 16. The recessed faces 14, 16 are surrounded by a pair of elongate, opposite side major walls 18, 20 and a pair of opposite upper and lower minor side walls 22, 24.

As can be seen in Figure 1 , the visual indicator device 10 further comprises a light reflector element in the form of a reflector plate/sheet 26, in particular a pair of first and second light reflector plates 26a, 26b, preferably retro-reflective plates, which are arranged to reflect light outwardly away from the housing 12.

The first reflector plate 26a is arranged to be accommodated in the front face of the housing 12. The first reflector plate 26a defines female openings at its corners 27 which correspond with the openings on the front face 14 of the housing 12.

The second reflector plate 26b is arranged to be accommodated in the rear face 16 of the housing 12. The second reflector plate 26b defines female openings 29 at its corners which correspond with the openings (not shown) on the rear face 16 of the housing 12.

The visual indicator device 10 comprises fixing elements 30, such as anti tempering fasteners, for example, rivets 30, for fixing the light reflector plates 26a, 26b to the housing 12. The fixing elements are arranged to extend through the openings 27 and 29 on the first and second reflector plates 26a and 26b, respectively, and the openings on the front and rear faces 14 and 16, respectively, of the housing 12.

The visual indicator device 10 also comprises a securing arrangement 28 for fixedly securing the visual indicator device 10 to the overhead conductor, as shown in Figure 3.

As shown in more detail in Figure 1 , the securing arrangement 28 comprises an open ended cylindrical member 32 that defines a bore. The cylindrical member 32 extends substantially transversely to the longitudinal axis A of the housing 12, and is positioned below the lower minor side wall of the housing 12 and arranged such that it is parallel to the operatively lower side wall 24 of the housing 12.

The securing arrangement 28 further comprises a first side cover 34 defining a first opening 36 and a second upwardly spaced opening 38 that is arranged to be co axial with the axis B of the cylindrical member 32.

The securing arrangement 28 further comprises a second side cover 40 having a locating member 42 for snugly fitting through the cylindrical member 32 and the second opening 38, thereby forming a first coupling arrangement that couples and locates the first side cover 34 relative to the second side covers 40.

The second side cover 40 also comprises a receiving element 44 that defines an opening with threads on an internal surface thereof. The receiving element 44 is arranged to receive a securing element 46, as will be described below. As can be seen in Figures 1 and 2, an anti-vibration washer 47 is provided between the first cover 34 and fixing element 46.

The securing arrangement 28 further comprises the securing element 46, such as a torque to break screw, that is arranged to be received through the first opening 36 and screw threadedly mated with the threads in the receiving element 44, so as to secure/fix the first cover 34 to the second cover 40, thereby forming a second coupling arrangement for coupling the first cover 34 to the second cover 40.

As can be seen in Figures 1 , 2 and 3, each operatively lower end of the first and second covers 34, 40 comprises securing gripping formations, in the form of elongate protrusions 46, 48, in particular gripping clips, which are shaped and sized to be snugly accommodated in a recess 72 defined on the overhead conductor 70. As can be seen in Figures 1 , 2, and 3 a first side cover 47 and a second side cover 49 flare downwardly from the lower minor side wall 24 and covers the longitudinal side of the cylindrical member 32.

In use, in order to secure the visual indicator device 10 to the overhead conductor 70, the locating element 42 on the second side cover 40 is pushed through the bore of the cylindrical member 32 and through the second opening 38 on the first side cover 34. Thereafter, the securing gripping formations 46 and 48 are located into their respective recesses 72 on the elongate sides of overhead conductor 70. The securing element 46 is then inserted into the first opening and threaded into the receiving element 46. The tension applied to the securing element 46 as it is threaded into the receiving element 44 causes the gripping formations 46 and 48 to be displaced towards each other thereby causing the gripping formations to grip firmly onto the overhead conductor 70. The housing 12 is accordingly arranged upright relative to the horizontally extending overhead conductor 70 in order to improve the visibility thereof. Accordingly, once the indicator device 10 is secured to the overhead conductor 70, the light reflector plates 26a and 26b are arranged upright or transversely relative to the horizontally arranged overhead conductor 70.

The visual indicator device 10 also comprises a condition monitoring system 50, which is fitted to the housing 12. The monitoring system 50 is arranged to continuously monitor a condition of the visual indicator device 10 and communicate same with a remote server 60, as shown in the network 56 which includes at least one visual indicator device 10 that communicates with the server 60 via a communication network 58. It will be appreciated that, although one visual indicator device 10 is shown herein, there can be multiple visual indicator devices in the network 56.

The monitoring system 50 comprises a communication module, such as a transceiver (not shown) for communicating in near real-time with a satellite (not shown) to receive a condition of the visual indicator device, in the form of a position signal of the visual indicator device 10, in near real-time. The monitoring system 50 further comprises a processor 52 and a memory device 54 that is coupled to the processor 52.

The server 60 may be connected to a database (not shown) or may have a memory device (not shown), for storing information that is associated with the visual indicator device 10, which information includes:

(a) the unique identification number of the visual indicator device 10;

(b) a reference GPS position of the visual indicator device 10 relative to the overhead conductor on which the visual indicator device is positioned, wherein the reference GPS position includes the X, Y, and Z (i.e., latitude, longitude, and altitude) coordinates of the visual indicator device when secured relative to the overhead conductor;

(c) a reference acceleration condition which is measured with reference to the X, Y, and Z coordinates of the visual indicator device 10 when the visual indicator device is secured relative to the overhead conductor; and

(d) a reference sensed condition, such as an impact pressure value of the visual indicator device when secured to the overhead conductor, which impact pressure value may typically be recorded as zero “0”.

The server 60 or database (not shown) in communication with the server 60 may also have information of other visual indicator devices 10 that may be secured to overhead conductor over a predefined geographic location.

In use, the processor 50 is arranged to receive the position from the transceiver (not shown), collect the reference position of the visual indicator device 10 from the server 60 or collect the reference position of the indicator device 10 from the memory device 54, and compare the received position to the reference location/position of the visual indicator device 10 in order to determine the near real-time position of the visual indicator device 10. In the event that the received position does not correspond with the reference position of the visual indicator device 10, the processor 52 is arranged to generate a signal that will be transmitted to the server 60. In the context of the present invention, it will be understood that the condition monitored by the monitoring system 50 in this instance is the GPS location of the visual indicator device 10.

The monitoring system 50 further comprises a detection element (not shown) comprising, for example, a pressure sensor (not shown), which is arranged to detect a condition of the visual indicator device, such as impact pressure applied on the visual indicator device 10, and compute the impact pressure into a pressure value. The processor 52 is then configured to determine whether the detected impact pressure exceeds a reference impact pressure value, and if so or if the detected impact pressure exceeds a predefined threshold, the system 50 is arranged to generate a signal and transmit the signal to the server 60.

In the context of the present invention, it will be understood that the condition monitored by the monitoring system 50 in this instance is the impact pressure applied to the visual indicator device 10. In use, when the impact pressure value exceeds the reference pressure value or a predefined threshold, this would provide an indication that the visual indicator device 10 is no longer positioned on the overhead conductor but may have crashed into the ground, or may provide an indication that a foreign object has struck the visual indicator device 10.

The monitoring system 50 further comprises an accelerometer device (not shown) which is arranged to measure an acceleration condition of the visual indicator device 10. The processor 52 is arranged to compare the measured acceleration condition of the visual indicator device 10 as measured by the accelerometer device (not shown) to the reference acceleration condition of the visual indicator device 10, to determine whether the measured acceleration condition corresponds with the reference acceleration condition of the visual indicator device 10. When the two conditions do not correspond, for example, when the acceleration of the visual indicator device 10 in one or more of the X, Y, and Z directions exceeds a predefined acceleration condition in a predefined period, for example when the gravitational acceleration of the visual indicator device 10 exceeds 60g in 1 6ms, the processor 52 is arranged to generate a signal and transmit same to the server 60.

In the context of the present invention, it will be understood that the condition monitored by the monitoring system 50 in this instance is the acceleration of the visual indicator device 10 in one or more of the X, Y, and Z directions, to provide an indication, in near real-time, of the movement and acceleration of the visual indicator device 10 relative to the reference GPS position and reference acceleration condition.

The server 60 may be arranged to transmit notifications to an inspectors’ unit and/or a security response unit when the server 60 receives the various signals from the monitoring system 50, in order to prompt the security response unit to further investigate the condition of the visual indicator device 10. Typically, the notification received by the response unit would include both the reference conditions (i.e. reference GPS position, reference impact pressure value, and reference acceleration condition) of the visual indicator device 10 and the conditions (i.e. GPS position, impact pressure value, and acceleration condition) of the visual indicator device 10 as determined in near real-time, in order to enable the security response unit to track the visual indicator device 10.

The server 60 is arranged to intelligently receive, in near real-time, all of the various conditions of the visual indicator device 10, that is collect the GPS coordinates, impact pressure, and acceleration condition of the visual indicator device 10 to make a determination of the overall condition of the visual indicator device 10. For example, the server 60 may have determined that the visual indicator device 10 was subjected to an impact pressure that exceeds the reference pressure value or pressure threshold value. However, rather than transmitting a notification to the response unit at that stage, the server 60 may be arranged to first determine the GPS location of the visual indicator device 10 to verify the position of the visual indicator device 10, and also determine the acceleration condition of the visual indicator device 10. In the event that the GPS position of the visual indicator device 10 corresponds with the reference position of the visual indicator device 10, and the acceleration condition of the visual indicator device 10 also correspond to the reference acceleration condition, then the server 60 can intelligently determine that the impact pressure sustained by the visual indicator device may not be related to the impact associated with the device crashing into the ground, and the notification sent to the response unit may include information that shows that the GPS location and acceleration condition of the visual indicator device correspond with the reference GPS position and reference acceleration condition, respectively, to enable the response unit to respond accordingly to the received notifications.

The advantage of using the GPS coordinates of the visual indicator device 10 in near real-time would assist in preventing the theft of overhead conductors, and accordingly the security response unit can react immediately in circumstances where one or more of the reference conditions of the visual indicator device 10 have changed, which would be indicative that the position of the overhead conductor may also have changed or indicative that the overhead conductor may have been tempered with.

It will be appreciated that multiple visual indicator devices 10 may be fitted on a single overhead conductor and may be spaced apart from one another by a predefined spacing. This may be necessary to ensure that the entire length of the overhead conductor is continuously monitored by the system 50 and server 60 in near real-time and thereby making the overhead conductor animate in near real-time and in all weather and lighting conditions.