Patent GB-191310063-A (GB)
Title: Improvements in Railway Signalling.
Inventor: TARRANT REUBEN WILLIAM
IPC: B61L23/12
Filed: 1913-04-29
Granted: 1913-08-21
Abstract: 10,063. Tarrant, R. W., and Sykes, J. C. April 29. Combined electrical and mechanical systems, non-automatic; track apparatus actuating signals other than on trains; signalling - instruments.-Relates to the improvements described in Specification 13,125/12, and consists in the provision of means for enabling cancellation to be effected electrically under the joint control of the operators at both ends of a block-section, a single line wire serving, if desired, for effecting cancellation on both tracks of a double-track road. The Figure shows the apparatus for use in normal working, as described in the abovementioned Specification, and in addition the cancellation - devices, operated over a common line wire w connected at both ends to pivoted transfer switches 100 which normally occupy the mid-position to connect at 102 to the block instrument at each end of the section. The switches are displaced to left and right at the train sending and accepting ends respectively when cancellation is desired. The terminals 104, 105 carry cancelling switches 107, 110 controlled by push-buttons 108, 111, which switches normally contact at 112, 114 with a line 116 leading to the earthed winding of a polarized relay 117, the armature 118 of which normally occupies a mid-position but is adapted to be displaced to make contact at terminals 120 or 126. One terminal 120 is coupled by a wire 121 to one of a pair of terminals 122, connected, when the lever 14 is back-locked, by a switch 124, to the wire 31. The other terminal 120 is connected by a wire 42 to terminals 40 normally disconnected by switch 37 from the wire 41. One terminal 126 is connected to contact 115 and the other to a terminal 129 normally connected by the home lever switch 71, the winding of the solenoid 60, or to a terminal 132 normally disconnected from the winding of the lock 55 by switch 131. To ensure that both ' line clear ' and ' line blocked ' indicators are returned before cancellation is made, the indicator members 21, 135, when in normal position, close contacts 137, 142 in the circuits from contacts 120, 126. The earth connexion 149 of the lock windings 20<a>, 20<b> contains a switch 150 normally closed by the cancelling-switch 107. If an operator at P wishes to cancel an acceptance, he communicates with A, and the indicators 21, 135 having been replaced, they move the switches 100 to right and left respectively, and B then presses the button 111. A current then passes from a battery 147, through switch 145, which has been closed by the fall of the plunger lock 59 when B accepted the train, switch 142, contact 115, switch 110, wire w, switch 100 at A, switch 107, wire 116, and relay 117 to earth return. The current moves the armature 118 to the left to close contacts 120. If the lever 14 at A has been set to ' line clear,' the backlock will now be released by current from battery 39 passing through wires 38, 48, switch 46, wire 35, switch 29, wires 31, 123, switch 124, wire 121, contacts 120, wires 125, 42, switch 37, wires 41, 34, winding 20<a> to earth; thus breaking the circuit and establishing the holding - circuit through winding 20<b> as described in the abovementioned Specification. A having returned the lever 14 presses the sending button 108 to break the circuit of winding 20<b> at 150 to relock the lever 14 and to energize relay 117 at B from battery 39 at A through wire 38, switch 37, wire 35, switch 29, wires 31, 123, 140, switch 46, wire 138, switch 137, wire 141, switches 107, 100, wire w, switches 100, 110 at B, wire 116, and relay 117 to earth. This current displaces armature 118 to the right to close contacts 126. If B had cleared his home signal, the back-lock on lever 49 will be released by current from battery 147, through switch 145, wire 143, switch 142, wire 148, contacts 126, wires 128, 133, switch 131, wire 73 to lock 55 and earth. On B returning the lever, the solenoid 60 is momentarily energized, to release the plunger lock. If B had not cleared his home signal, the plunger lock 60 will be directly released by current from battery 147 passing through switch 71 to the winding of the solenoid 60. The provision of a front lock for the levers 49 does not affect the operation.