The present invention relates to a device to eliminate the tinne delay while observing calling on signal at a railway station. Calling on signal is an ancillary Railway signal fixed below the main signal at a Railway station. Calling on signals are used when all conditions to clear the main signal are fulfilled except the track circuit failure on the route. Under such condition the main signal does not work.
To avoid piloting of trains due to main signal failure, calling on signals are used. Since there is a possibility that the line may be occupied by a train/vehicle, the train is permitted to approach the route at a restricted speed of 10 kmph._This can avoid train collision. But how to ensure that the driver will go only at 10 kmph ? Therefore, before clearing a calling on signal, the train is brought to a stop, made to wait for 2 minutes in rear of the calling on signal and only after lapse of the time delay, the calling on signal is cleared. Since the driver has to start from rest, he can ensure 10 kmph speed ahead in the station area. Net result is that the train is getting delayed whenever calling on signal is given in railway stations.
Hence we have come out with a state of the art device to eliminate the time delay while observing calling on signal at a railway station. Because of this invention we can eliminate the 2-minute delay of every train when using calling on signal and also ensure that the prescribed speed limit of 10 kmph is not exceeded thus ensuring full safety.
This device is an add-on facility to the existing automatic train control system, which will eliminate the time delay while calling on signal is used. This device consists of a selection logic device comprising of relays or micro controller/micro processor.
Accordingly the present invention consists of a device to eliminate the time delay while observing calling on signal at a railway station adaptable to the automatic train control system comprising a calling on signal selection

logic device (1) capable of taking the input fronn the train inter locking system (2) and the station master's control panel (3) and verifying all the condition for the passage of the train is clear except the track circuit failure, there by generating a digital out put for sending to line side electronic unit (5) which is preprogrammed in such a way enabling to generate a telegram with the message to indicate that train is being received on calling on signal and with speed limitation to be conveyed to the balises/ RFID (6) and (7) for onward transmission to the train where in the onboard equipment is capable of automatically regulating the speed limit.
Now the invention will be described in more detail with reference to the accompanying drawings, bringing out a number of embodiments of the arrangement according to the invention.
Fig.l Block diagram of a device to eliminate the time delay while observing calling signal at Railway Stations. Wherein
1. Calling or Signal selection logic device of this invention.
2. Existing Interlocking system
3. Station master control panel
4. Digital output from device
5. Line side electronic unit (LEU)
6. Train control system balises / RFID
7. Train control system balises / RFID
8. Main signal
9. Calling as signal
10. Warning signal
11. Track Circuit on the route where failure has invoked the use of calling on signal.
Ref. to Fig.l. The input to the device is from the existing interlocking system and the station master control panel. The inputs thus taken from the interlocking system is processed by the selection logic device, to produce a digital output. The digital output is derived only when the calling on signal

conditions are fulfilled plus the main signal is at ON (red) condition and there is a command from the station master control panel to operate the calling on signal. The digital output is used to generate a telegram in the LEU of the train control system. This telegram contains the information regarding the speed profile along the route to be followed by the main ie. Reduce the speed from the maximam spped to 10 kmph at calling on signal and maintain 10 kmph beyond the calling on signal. Because of this, now the train control system will not only display the speed profile but also will enforce the same. Since enforcement of 10 kmph is assured and maintained, there is no need for the train to stop and wait for 2 minutes at the calling on signal. The calling signal selection logic device is having a set of relays, micro controller, microprocessor, with electric network, connected to the train inter locking equipment and the station master control panel.
An added feature of this invention is the incorporation of fail safe system in the selection logic circuit which canot generate the digital out, unless it satisfy the specified condition.
In a preferred embodiment as per our invention the line side electronic unit is capable of providing the text display to the driver in the control panel of the train is received on calling as signal.
Although the invention has been described in considerable detail with particular reference to certain preferred embodiments thereof, variations and modifications can be effected within the spirit and scope of the invention as described herein above and as defined in the appended claims.

We claim
1. A device to eliminate the time delay while observing calling on signal at a
railway station adaptable to the automatic train control system comprising
a calling on signal selection logic device (1) capable of taking the input
from the train inter locking system (2) and the station master's control
panel (3) and verifying all the condition for the passage of the train is
clear except the track circuit failure, there by generating a digital out put
for sending to line side electronic unit (5) which is preprogrammed in such
a way enabling to generate a telegram with the message to indicate that
train is being received on calling on signal and with speed limitation to be
conveyed to the balises/ RFID (6) and (7) for onward transmission to the
train where in the onboard equipment is capable of automatically
regulating the speed limit.
2. The advice as claimed in claim 1 where in the onboard equipment in the train is capable of regulating the speed not exceeding 10 Kmph based on the telegraphic message received from the line side electronic unit.
3. The device as claimed in claim 1 where in the calling signal selection logic device is having a set of relays, micro controller, microprocessor, with electric network, connected to the train inter locking equipment and the station master control panel.
4. The device as claimed in claim 1 the said selection logic circuit has fail
safe system where inbuilt design will not generate the digital out, unless it
satisfy the specified condition.
5. The device as claimed in claim 1 where in the line side electronic unit is
capable of providing the text display to the driver that the train is
received on calling as signal.
6. Equipment as claimed in claim 1 to 5 substantially herein described with
reference to and as shown in FIG 1 of the accompanying drawings.