GB138208A - Improvements in or relating to railway signalling apparatus - Google Patents

Abstract

138,208. Sykes Interlocking Signal Co., W. R., Tiddeman, E. S., and Russell, F. V. March 19, 1919. Track apparatus for stopping trains.-In apparatus of the kind in which danger-signals or train-stopping apparatus are operated by mechanical means at each track ramp unless an electro-magnetic restraining-device is energized by current received from the track ramp through the mechanical contact device such as is described in Specifications 6499/15 and 112,191, the plunger is locked in its raised position at a danger home signal but not a clear home signal, nor at a distant signal at which the plunger is raised a less distance than at a home signal. The latch can only be released by the driver after dismounting from the locomotive. At a distant signal, the brakes may be only partly applied, and different whistles are sounded at home and distant danger signals. Danger signals are operated if the contact shoe is broken. The shoe 16 is carried by a plate 11 adjustably mounted on a plate sliding in vertical guides on the base 13. This plate carries a stop 22 and a bell-crank 20 which holds the lever 17 in position to maintain closed the valve 39, which is also controlled by the electro-magnet 31 as described in the prior Specification. The plate 11 also carries an arm 71 with a pin 70 coacting with a slotted valve spindle 64, so that the valve connects the brake-venting pipe 42 to one whistle pipe 68 when the plunger is in its lowered position or in the position to which it is raised at a distant signal, and to another whistle pipe 67 when the plunger is raised at a home signal. A spring- pressed latch 46 is arranged to enter the slot 50 in the plunger when this is raised at a home signal, but is held out of action, if the signal is clear, by a pawl 59 carried on the spindle of the lever 17 engaging a sliding rod 51, which serves as a latch-releasing member after operation. Fig. 8 shows the lever 20 supported by a bell-crank 72 instead of by the fixed stop 22. This bell-crank is held in position by the rod 74, 75 attached to the shoe 16, so that if the shoe is broken away, the brakes will be applied.