Patent GB-353901-A (GB)
Title: Improvements relating to train describing apparatus
IPC: B61L25/08
Filed: 1930-04-29
Abstract: 353,901. Electric signalling systems. ANDERSON, C. N., 28, Ravenscourt Gardens, Hammersmith, and SYKES' INTERLOCKING SIGNAL CO., Ltd., W. R., 26, Voltaire Road, Clapham, both in London. April 29, 1930, No. 13102. [Class 40 (i).] At the receiver of a step-by-step system for transmitting an indication of particulars of a train from one signal cabin to another, a slow-acting relay which controls the printing of the indication is governed jointly by the movement of the typewheel and by a normally energized relay which is de-energized by the first movement of the typewheel and re-energized after the printing-operation. In the construction shown, apparatus at the receiving point comprises an electromagnet 5 the armature 6 of which is connected to a rod 11 attached to a slidable frame 12. This frame is provided with pawls 14 for engagement with a ratchet wheel 15 secured to a spindle carrying a printing wheel 17. The inner face of the ratchet wheel is provided with pins 20 between which project one or other of two teeth 21 attached to the frame 12. The wheel 17 is provided with type blocks 22 corresponding to particular train descriptions. A paper record strip 25 unwound from a reel 24 passes behind the wheel 17 and is adapted to be unwound by means of a roller 27 which is rotated step-by-step by ratchet and pawl mechanism controlled by an electromagnet 38. The armature 37 of the electromagnet is adapted, when energized, to operate a plunger 32 so as to press the record strip against the lowermost type block on the wheel 17. The electrical connections at the transmitting and receiving points are shown in Fig. 3. Operation of an impulse transmitter 44 at the transmitting point A causes at the point B corresponding movement of the armature 6, whereby the printing wheel is rotated intermittently to bring the corresponding type block to the lowermost position. The armature 6 controls the opening and closing of contacts 51, 52, 53. Contacts 51 when opened cause the de-energization of a normallyenergized relay 46, whereby contacts 47 are opened and contacts 48 are closed. Contacts 48 prepare the circuit of a slow-acting relay 49 which is energized, through the medium of contacts 53, each time the armature 6 returns to normal, but does not close its contacts 50 until the impulses transmitted to the electromagnet 5 have ceased. The closure of contacts 50 causes electromagnet 38 to be energized whereby the type block 22 prints the description on the record strip 25. The movement of the armature 37 closes contacts 54 to re-energize the relay 46, which at contacts 48 opens the circuit of relay 49 causing the magnet 38 to release the armature 37. This effects a step in the rotation of the roller 27, Fig. 1, whereby the strip 25 is moved to expose the printed description. An indication to the transmitting point that the recording has been effected is transmitted through the medium of contacts 52, 55 associated, respectively, with armatures 6, 37, for the purpose of completing circuits through a polarized relay 62. Closure of contacts 52 causes the armature 63 to engage contact 64 whereby the pointer 67 of an indicator 66 is moved one step for each movement of the type-wheel 17. On the completion of the movements the closure of contacts 55 causes the armature 63 to engage contact 65 whereby a bell 68 rings to indicate that the printing on the strip 25 has been effected. The apparatus may be combined with mechanism for causing the time of receipt of a train description to be printed adjacent to the description.