The Locomotive Of Today

The Framing, Wheels, etc. : Buffers, Couplings. 153 A type of buffer used on the Continent is illustrated at G. In this the casing is similar to that last described, but the back plate is of cast iron formed to receive the nut on the centre bolt and allow of its travel when the buffer is com- pressed ; the spring in this case is made up of a number of separate dished discs placed upon the centre pin with their curved faces arranged to meet alternately. There are innumerable other designs of buffers, but the principles underlying all of them are the same as those illustrated. Many have indiarubber cushions instead of Steel springs, this material being very suitable for withstanding the severe and sudden shocks to which the buffers are subjected in service, and which often prove fatal to Steel springs. A screw coupling is drawn at H. The draw hook has a shank which passes through the buffer beam at the centre of the engine, and has Steel springs as shown or indiarubber cylinders held by a nut and split pin. Through a hole in the hook a link of the shackle is passed, a swivel being attached to the two ends of the shackle securing them and the screw together. The screw is revolved by means of the hanging arm, and turns in a nut fixed to the other link of the shackle; this second link is hooked upon the next vehicle, and as the screw is turned the necessary tension is secured, whilst the weight hanging clown prevents the screw from slacking back in running. On narrow gauge stock the side buffers are usually dis- pensed with, and the draw hook is made in the form of a combination of buffer and hook, the only point of contact being, therefore, on the centre line of the train. This is no doubt the most suitable place for this purpose, as the power required to compress the inside buffers of a long train when taking a curve is very great, and entails consiclerable work upon the engine. In America the central combined method of attachment and buffing is universal both for goods and passenger service, the couplers of adjacent vehicles coupling on impact, and being uncoupled by means of a lever at the side. There is thus no necessity for anybody to go between for coupling or uncoupling. The extra flexibility obtained by the use of this method of attaching the several vehicles together, added to the flexible wheel base of all the stock, makes the American train, although heavier in build, comparatively easy to haul. Having dealt now with practically all the working parts of the mechanism of the engine, Reference must be made before concluding the section on the running gear, etc., to that necessary item, lubrication. The lubricating medium—oil,