AUTOMATED PAPER LINE CLEARANCE DEVICE.
Complete Specification:
This Invention relates to improvement of Safety of Trains when they have to operate under Paper Line Clearance system of Railway Signaling, when there is a failure in the normal Block Working.
Safe Operation of Trains by the Railways is ensured by Signaling systems known as Absolute Block Signaling System, Intermediate Block Signaling System and Automated Block Signaling System. A Block is the length or portion of the Railway track on which only one train is allowed at any given point of time. A train is not allowed to enter into a Block in which a train is already present.
In a Single line system, there is only one railway track connecting two stations and the same track is used for running trains in both directions between the stations. In a Double Line system, there are two Railway Tracks connecting two stations. One track is dedicated for a train going from Station A to Station B and the other is dedicated for trains running from Station B to Station A.
In any Block system, a train can be allowed to enter into a Block only when it is established that there is no train on the Block Section ahead. Safe train movement, in

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the Absolute Block Working system is controlled by a Pair of Block Instruments, one at each station.
Normal Block Working can be disrupted when :
• There is a failure of Signals authorizing Trains to Pass
• Block Instrument failure.
• Faults or temporary shut down of one line of a Double Line system, thereby forcing the remaining line to be used for train movement in both directions.
• Usage of Trolleys for inspection or repair on a line.
In case Normal Block Working is disrupted, train movement is not completely halted but is still maintained under manual supervision. The authority for a train to proceed when normal Block working is disrupted, is done under a system called Paper Line Clearance. This clearance for a train to proceed is a handwritten form, called a Paper Line Clear Ticket, is filled in by the Station Master at the originating station, after ascertaining that the Block ahead is vacant. This Paper Line Clear Ticket is handed over to the Train Driver, authorizing him to proceed to the next station. The Train Driver hands over the Paper Line Clearance Ticket to the Station Master at the Destination Station. The authorization for the next train to enter into the Block is given only after the Paper Line Clear Ticket is received and acknowledged by the Station Master of the Destination Station.


However, there have been accidents caused due to human error, where Paper Line Clearance was inadvertently given to two trains, from both Originating and Destination Stations for the same line in the same Block Section, resulting in a collision.
The said invention increases the Safety of Train Operations by automating the process of issuing Paper Line Clearance and by restricting issuance of another Paper Line Clear Ticket by anyone else, for the Block where a Paper Line Clear Ticket has already been issued.
To assist with understanding the invention, reference will now be made to the accompanying drawings, which show examples of the invention.
The General Arrangement of the invention, Automated Paper Line Clearance Device, used in a Block Working section is shown in Figure -1, showing Station A (1), Station B (2), the railway track (3) connecting them, a Pair of Paper Line Clearance Machines PLCM-A(4) and PLCM-B (5). Communication between the two stations is by means of Wireless Media(6), Copper Cable Media(7) and Optical Fiber Media (8),
The Automated Paper Line Clearance Device refers to a pair of Paper Line Clearance Machines (PLCM), one of which is shown in Figure-2 . Each Pair of PLCMs has a Unique Code, The pair of PLCMs interact with each other and perform the task of


issuing Paper Line Clear Tickets in the formats as prescribed by the Railways. The communication method is as selected from Copper Cable (7), Optic Fiber Cable (8) or Wireless Media (6) comprising of GSM-R, GSM, Data Radio inVHF/UHF, CDMA, Satellite Communication, and WiMax.
The Paper Line Clearance Machine (PLCM) shown in Figure-2, consists of an Operating Module(9), A Central Processor Module(lO), a Communication Module (11) and a Power Supply Module (12).
The Operating Module (9) as shown in Figure - 2, has a Name Plate (13), which has the Unit Number, the name of the Originating Station and the name of the Receiving Station. A Station Master Key (14) is provided for preventing unauthorized access. There is a Mechanical Counter (15) linked to the key to count and record the number of times the key is used. A Bar Code Reader (16), a Display (17) and a Keypad (18) for data entry are provided. There is an inbuilt Printer Slot (19) to accommodate a Printer to print the Paper Line Clearance Ticket. The Paper Line Clearance Ticket printed from this PLCM will contain a non repeating Random Number, A unique Barcode and the Identity Code of the that PLCM. When the Operating Module of one PLCM in the Originating Station, is activated to print a Paper Line Clearance Ticket, the pair PLCM in the Destination Station is interlocked so that another Paper Line Clearance Ticket cannot be activated or printed.


The Central Processor Module (10) as shown in Figure-2, is an embedded microprocessor based electronic module with appropriate software programs for it's fiinctioning. It has Ports (23) for input and output and has a memory to log and store events. It has Coloured LED Lamps for displaying Status like System Health (20), Lock Activation (21) and Fault (22).
The Communication Module (11) as shown in Figure-2, is an electronic module with appropriate software to handle communication with the Central Processor Module and its pair PLCM at the receiving Station. It has Coloured LED lamps for displaying Pair Ready (24) status and a Buzzer (25), Communication Ports (26) are provided for Wireless media. Copper cable media and Optical Fiber Media.
The Power Supply Module (12) as shown in Figure-2, provides voltage and currents as required by the other modules of the PLCM. It is provided with an On/Off Switch (27) with appropriate Coloured LED lamps to display the status of various outputs.
The Paper Line Clearance Ticket (29) printed by the PLCM as shown in Figure-3, has all the information (30) that the traditional Paper Line Clearance Ticket contains. The Private Number (31), which is part of this information, is generated by the microprocessor by a Random Number Generator. In addition, to this the Paper Line Clearance Ticket printed by the PLCM also contains the unique Identification Code (32) of the Pair and a Bar Code (32), which is derived from the Private Number.

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Figure - 4 is an embodiment of the invention, used in a Single Line Block Working section, between Station A(33) and Station B (34), with a single line (37) Connecting them. Trains (34) and (35) are shown at the stations. PLCM-A(38) and PLCM-B(39), connected via the chosen Communication Media(40), PLCM-A and PLCM-B are always in switched ON mode.
Under normal conditions. Train movement is maintained through Signals and Block Instruments between Station A and Station B. In the event of a situation where it is necessary to control train movement through issuance of a Paper Line Ticket, the Concerned Authority uses the Automated Paper Line Clearance Device.
If the paper Line Clear Ticket is to be issued at Station A(33) for the Train (35) to proceed to Station B (34), the User at Station A, operates the Key(14) shown in Figure-2, to gain access to operate the PLCM-A. The Display (17) prompts him to enter his password through the Keypad(18). On authentication of the password, PCLM-A communicates with PCLM-B at Station B. Once communication is established, the Pair Ready Lamp(24) glows on both and the Buzzer (25) gives an audio signal.
PCLM-A Operator presses ACK key on Keypad (18), to turn off the Buzzers and also to Lock the PCLM-B, so that PCLM-B cannot issue a Paper Line Clearance Ticket. The Lock Activated Indication(21) is now ON at both, PCLM-A and PCLM-B.


PCLM-A is now ready for issuing a Paper Line Clearance Ticket to authorize Train(35) to proceed to Station B.
The Operator at Station A, keys in the data that is required to generate the Paper Line Clearance Tidcet. Once the process of data entry is completed and submitted by the Operator, the Processor Unit generates a Random Number, which is the Private Number that will be printed on the Ticket. A combination of the PCLM-A Unit Number and the Private Number is used to create a Bar Code that is also printed on the Ticket. The Paper Line Clearance Ticket (41) is Printed when the Operator presses the Print Key on the Keypad.
This Paper Line Clearance Ticket (41) is now carried by the Train Driver and is handed over at the destination Station B (34),
The Operator at Station B, receives the Paper Line Clearance Ticket (41). He then keys in the Private Number into the PCLM-B and swipes the barcode over the Barcode Reader on PCLM-B. This information is compared with what has been received from PCLM-A, Once this information is tallied and found correct, PCLM-B communicates to PCLM-A, that the Train from Station A has arrived and that the block is free. Both PCLM Units are normalized. The PCLM-B can is now free to issue a Paper Line Clearance Ticket for train (36) going to Station B, after locking the PCLM at Station A, using the same procedure.


In case of total communication failure between the two stations, wherein the pair of PCLMs cannot communicate with each other, there is an emergency mode in which, a Paper Line Clearance Ticket can be issued, in conjunction with the Train Controller who can contact both stations. In this mode, the Train Controller authorizes one of the Stations to dispatch a train. The User in the train Originating Station A, then keys in the emergency mode into the PLCM-A. In this mode, a pair of Private Numbers is taken from identical tables stored in the pair PCLMs. The Paper Line Clearance Ticket is printed with the first one of the Pair of Private Numbers stored in the PCLMs. The Paper Line Clearance Ticket is handed over to the Train Driver, who in turn hands it over to the Destination Station-B. The Private Number is then keyed into the Pair PCLM-B, which compares it with the first number of the pair Private Number present in the stored Table. When they match, the PCLM-B at the Destination Station displays the second number of the stored Pair. This second number is communicated to the Controller, who in turn communicates this to the Originating Station-A. This number is keyed into the PCLM-A at the Originating Station to acknowledge Train arrival at Destination Station. The PCLM-A is normalized when the number matches with the second number of the stored pair.
Figure-5 is an embodiment of the invention, used in a Double Line Block Working section between Station A(42) and Station B (43). The line (44) is for trains from Station A to Station B, and the line (45) is for trains from Station B to Station A.


Trains (46) and (47) are shown at the stations, PLCM-A(48) and PLCM-B(49), connected via the chosen Communication Media(50). PLCM-A and PLCM-B are always in switched ON mode.
Under normal conditions, Train movement is maintained through Signals and Block Instruments between Station A and Station B, in the specified direction. In the event of a situation where one line is temporary shut down in the Double Line system, the remaining line has to be used for train movement in both directions. Assuming that the line (44) is not to be used, then line(45) has to be used for trains traveling in both directions.
If the paper Line Clear Ticket is to be issued at Station A(42) for the Train (46) to proceed to Station B (43) through line (45), the User at Station A, operates the Key(14) shown in Figure-2, to gain access to operate the PLCM-A, The Display (17) prompts him to enter his password through the Keypad(18), On authentication of the password, PCLM-A communicates with PCLM-B at Station B. Once communication is established, the Pair Ready Lamp(24) glows on both and the Buzzer (25) gives an audio signal.
PCLM-A Operator presses Ack Key on Keypad (18), to turn off the Buzzers and also to Lock the PCLM-B, so that PCLM-B cannot issue a Paper Line Clearance Ticket. The Lock Activated Indication(21) is now ON at both, PCLM-A and PCLM-B.


PCLM-A is now ready for issuing a Paper Line Clearance Ticket to authorize Train(46) to proceed to Station B.
The Operator at Station-A, keys in the data that is required to generate the Paper Line Clearance Ticket, including the details of the line on which the train is authorized to travel. Once the process of data entry is completed and submitted by the Operator, the Processor Unit generates a Random Number that is the Private Number that will be printed on the Ticket. A combination of the PCLM-A Unit Number and the Private Number is used to create a Bar Code that is also printed on the Ticket. The Paper Line Clearance Ticket (51) is Printed when the Operator presses the Print Key on the Keypad.
This Paper Line Clearance Ticket (51) is now carried by the Train Driver and is handed over at the destination Station-B (43).
The Operator at Station B, receives the Paper Line Clearance Ticket (51). He then keys in the Private Number into the PCLM-B and swipes the barcode over the Barcode Reader on PCLM-B. This information is compared with what has been received from PCLM-A. Once this information is tallied and found correct, PCLM-B communicates to PCLM-A, that the Train from Station A has arrived and that the block is free. Both PCLM Units are normalized. The PCLM-B can is now free to


issue a Paper Line Clearance Ticket for the train (47) going to Station B, after locking the PCLM at Station A, using the same procedure.
Means are also provided to handle Double Line Working in case of total communication failure between the two stations, wherein the pair of PCLMs cannot communicate with each other. There is an emergency mode in which, a Paper Line Clearance Ticket can be issued in conjunction with the Train Controller who can contact both stations. In this mode, the Controller authorizes one of the Stations to dispatch a train. The User in the train Originating Station A first keys in data to enter into the Emergency Mode and then keys in the Line Details along with other details required for generating the Paper Line Clearance Ticket. In the emergency mode, a pair of Private Numbers is taken from identical tables stored in the pair PCLMs. The Paper Line Clearance Ticket is printed with the line on which the train has to travel and the first one of the Pair of Private Numbers stored in the PCLMs.
To ensure that the train is on the correct line, the Paper Line Clearance Ticket is handed over to the Train Driver only after it is physically confirmed by the Authorized Person, that the train is on the correct line, as indicated in the Paper Line Clearance Ticket. The train driver hands the Paper Line Clear Ticket to the Destination Station-B, on arrival. The Private Number is then keyed into the Pair PCLM-B, which compares it with the first number of the pair Private Number present in the stored Table. When they match, the PCLM-B at the Destination Station


displays the second number of the stored Pair. This second number is communicated to the Controller, who in turn communicates this to the Originating Station-A, This number is keyed into the PCLM-A at the Originating Station to acknowledge Train arrival at Destination Station. The PCLM-A is normalized when the number matches with the second number of the stored pair.
Provision is also given in the Automated Paper Line Clearance Device for recalling and canceling the Paper Line Clearance Ticket, in case the train with the Paper Line Clearance Ticket, for any reason, is forced to return to its Originating Station.

We Claim:
1. An Automated Paper Line Clearance Device to improve safety of Train operations, Comprising of a pair of Paper Line Clearance Machines comprising of Operating Module, Central Processor Module, Communication Module and Power Supply Module, with appropriate software programs, interconnected and interacting with each other to perform the task of improving the Safety of Train Movement when Trains are operating under Paper Line Clearance, by automating the process of issuing Paper Line Clearance and by also Automatically restricting issuance of another Paper Line Clear Ticket by anyone else, for movement of another train in that Block, once a Paper Line Clear Ticket has already been issued for that Block section.
2. The Automated Paper Line Clearance Device claimed in Claim (1), improves the level of safety by eliminating the human element of error by automating the issuing of Paper Line Clearance Tickets, that is currently done manually.

3. The Automated Paper Line Clearance Device claimed in Claim (1), wherein it can be used in both Single and Double line Block Sections to improve the level of safety by automating and restricting the issuing of Paper Line Clearance Tickets.
4. The Automated Paper Line Clearance Device claimed in Claim (1), improves the level of safety by ensuring that once one of a pair of PLCMs starts the process of issuing a Paper Line Clearance Ticket from the Originating Station, the pair PLCM at the Destination Station is interlocked so that it cannot issue another Paper Line Clearance Ticket for the same Block section, unless the Paper Line Clearance Ticket from the Originating PLCM is physically received, matched for Barcode, Unit Number and Private Number.
5. The Automated Paper Line Clearance Device claimed in Claim (1), improves the level of safety by ensuring that once one of a pair of PLCMs starts the process of issuing a Paper Line Clearance Ticket from the Originating Station, the same PLCM at the Originating cannot issue another Paper Line Clearance Ticket for the same Block section, unless the Paper Line Clearance Ticket from the Originating PLCM is physically received, matched for Barcode, Unit Number and Private Number by the pair PLCM at the Destination Station.
6. The Automated Paper Line Clearance Device claimed in Claim (1), where a non repeating Random Number (Private Number) on the Paper Line Clearance is

automatically generated by the PLCM at the Originating Station, and compared with that issued or received by itself or its pair over the last 30 days, and accepted and printed only after this check, this said Private Number being transmitted to the pair PLCM at the Destination Station,
7. The Automated Paper Line Clearance Device claimed in Claim (1), wherein there is a means of printing a Paper Line Clearance Ticket in emergency mode; when there is block failure because of compete communication breakdown between the train Origin Station and Destination Station.
8. The "Automated Paper Line Clearance Device " according to any of the Claims from 1 to 8, substantially as herein described with reference to and as shown in Figures 1 to 5 of the accompanying drawings.