Patent GB-116918-A (GB)
Title: Improvements in Signalling and Train-stopping Apparatus.
Inventor: WHYTEHEAD ERIC HARTWIG
IPC: B61L3/02
Filed: 1917-06-23
Abstract: 116,918. Whytehead, E. H. June 23, 1917. T r a c k apparatus actuating signals on trains and for stopping trains.-The supply of operating fluid to mechanisms operating signals or traincontrolling valves is controlled b y a n initiator valve which is normally closed by the operating fluid a n d is positively opened by the movement of the train contact member at a track obstacle. The initiator is moved to an operative position if the contact member is broken. The initiator reverses the supply of fluid pressure to two signal- or valve-operating cylinders under control of a selector device which may be controlled from the track either electrically or mechanically so as to allow the operation of either clear signals or danger signals and train-controlling valves on the train. The initiator and the danger-signal apparatus and valves are locked after operation until manually reset. The resetting device may be controlled by the lever controlling the motive power of the train, so that the motive power must be shut off before resetting the apparatus. It may also be dependent upon a speed-controlled element, so that the apparatus may be reset only after a predetermined reduction of speed. The contact carried by the train, as shown on Fig. A, comprises a spring- pressed sliding bar 118 carrying a roller 200 which runs on the inclined rail D. The axle 203 of the roller 200 is extended and supports the forked lower end of a rod 13<1> sliding in guides on the rod 118 and carrying an insulated ramp T at its upper end. The ramp T and the rod 13<1> are thus raised at each track rail whilst, if the roller axle is broken or becomes detached, the rod 13<1> falls and the ramp T falls clear of the valve controlled by it. The ramp T, (Fig. 1), normally holds the initiator valve in the inoperative position shown, in which it is pressed against the ramp T by fluid pressure. Fig. 1 shows a piston valve used in an apparatus employing pressure fluid. Alternatively, a similar valve may be used on a vacuum brake system, or either valve may be replaced by a rotary valve. As shown in Fig. 1, the fluid pressure from the pipe F passes through the pipe 4 and the port 6 to the outer ends of the cylinders C, C', forcing the two pistons inwardly. When the ramp T is raised, the initiator valve is moved inwards and the inner ends of the cylinders C, C' are subjected to pressure through the pipe 8 and port 10, the outer ends being exhausted through the ports 48, 49. The piston-rods 19, 19<a> carry teeth 24, 25, one of which engages the selectorhead 26 according to the position of the selector S. This member may be moved electrically or mechanically by co-action of apparatus on the track which is energized or moved according to the state of the track. As shown, the electro-magnet M is energized through the rail D and the contact rod 118 when the track is clear, and then serves to raise the selector head 26 to stop the movement of piston-rod 19 and allow the pistonrod 19<a> to move outwards, thus opening the pipe 12 and whistle W to fluid pressure and giving a clear signal. If the track is blocked, the selector head remains as shown and the piston-rod 19 is moved outwards and operates the valve V of another audible signal or any other suitable danger signal or the brake valves or motive-power controller of the train. The electro-magnet M may operate visible signals 33, 34 and may receive its energy directly from a source on the track through the rail D or from a local source of energy controlled bv the track rail circuit. The initiator valve and the danger-signal piston-rod 19 are held in their operated positions by pawls 44, 35, engaging teeth 29, 46. The pawls are released by the manual operation of the rod 37. The arm 41, pivoted to the rod 37 is moved from its free position to engage the pawl 35 bv a rod 55 connected to the lever L of the motive-power valve or brake valve so that the pawl may only be released when this valve is shut. The lever 55 may also be subject to speed-governor control. In the event of damage to the rod 118 or 13', the ramp T falls away and the initiator valve is moved outwardly by pressure on the piston, and pressure passes from the pipe F to the outer ends of cylinders C, C', causing actuation of danger signals on the train.