Patent GB-191114593-A (GB)
Title: Improvements in and relating to Lock and Block Signalling Systems and Apparatus for Railway Signalling.
Inventor: NEELE CHARLES WOODWARD
IPC: B61L23/12
Filed: 1911-06-20
Granted: 1912-05-02
Abstract: 14,593. Neele, C. W., and Reed, F. W. June 20. Combined electrical and mechanical systems, non-automatic; hand-levers; signalling-instruments.-In a lock and block system, the current in the line circuit through three-position indicators is reversed when a train enters a section, by de-energization of a track relay, in conjunction with the armature of a line relay which is adapted to be actuated by the plunger of the block instrument at the receiving-end of the section. The lever for the starting-signal at the sending end of the section is unlocked by the armature of an electro-magnet in a circuit controlled by a polarized relay in the line circuit or an electro - magnetic slot may be energized by this circuit. The signals 'train ' on line ' and ' line blocked ' are given automatically, but ' train on line ' at the receiving end may be given by manual operation of a switch, which prevents sending a ' line clear ' signal by locking the plunger and de-energizes the track relay. Contacts controlled by the hand-lever for the home signal and the track relav break the line circuit until the train has cleared the section and the signal is reset to danger. A modification is described for use with a block section divided into two short sections so as to enable two trains to be in the section at once if desired. A switch is provided to change over from one long section to two short sections as required. Fig. 1 shows one section for working from A to B with three-position indicators 42, 21, starting-signal 120 at A, the lever for which is controlled by the pendulum 70, see Fig. 8, and the home signal 122 at B controlled by the lever 23. The apparatus is shown in normal position with the track clear. To pass a train from A to B, ' line clear ' is given from B by pressing plunger 2, thereby closing contacts 8 in a circuit from earth at 61, contact 37 of track relay 35, wire 62, battery 55, wire 56, magnet 6, instruments 21, 42, and polarized relay 43 to earth. The polarized relay 43 closes the contacts 64, so that, by depressing the push 44, the signal-lever for the starting-signal 120 is released bv the magnet 25 attracting the pendulum lock 70. The contact 8 is kept closed by the magnet 6. When the train passes the insulation 77<a> into the block, the relay 35 is short-circuited and the contact 37 is opened and 38 closed. The line circuit is broken, and the magnet 6 releases its armature, the joint effect being to reverse the current in the line circuit from earth at 61, contact 38, wire 72, battery 55, contact 11, indicators 21, 42, magnet 43 which opens the circuit of the locking - magnet. The signal ' train on line ' is thus given automatically. The contacts 40 which are closed by the deenergization of the relay 35, complete a circuit from the battery 81, over the contacts 31, magnet 26, wire 84, contacts. 40, wires 85<a> and 85 thus energizing the magnet 26, which releases the catch 78 on the bar 28, which is moved by springs when the signal-lever 23 is pulled off, breaking the last-mentioned circuit and closing the contacts 34, which shunt the relay 35 until the signal-lever is replaced. The bar 28 is then pushed back by the engagement of a projection on the slide 27 with the roller 150 and makes the contacts 31, and is locked by the counterweighted armature of the magnet 26. The relay 35 is re-energized when the lever 23 is replaced if the train has cleared the section and the line circuit is broken at the contact 38. The indication line blocked ' is thus given automatically. If desired, the signalman at B can set the switch 1 at ' train on line ', by turning it through a right-angle, thereby breaking the track-relay circuit at contacts 18, and maintaining ' train on line ' until the switch is replaced. The spindle of switch 1 carries a disk with a notch in its edge, through which a projection on the plunger 2 passes only if the switch 1 is normal. Springs acting against a squared portion of the spindle hold the switch in its two operating positions. According to the Provisional Specification, the switch 1 and the plunger 2 may be replaced by a three-position switch.