The Locomotive Of Today

148 The Framing, Wheels, etc. : Radial Axleboxes. they can slide in curved guides, attached to the engine-frames, and are thus prevented from partially revolving about the centre of the pair of wheels. At E is shown one form of such a radial box, in plan, half section and lialf elevation. The curved guides are made of Steel frame plate, and are bent to the required shape and radius, usually in a hydraulic press; they have sliding between them the axle box which is wide enough to reach across from one journal to the other, and has fitted in it gun-metal bearings for each journal. As a pair of wheels such as shown at E, require a large amount of side play, about ij-in. upon each side of the centre is often allowed, and some form of controlling gear fitted to make them keep a steady central position when the engine is upon a straight road. In the type under notice this gear is in the form of an elliptical spring laid upon its side ; the axle box having underneath at each side of the centre, lugs projecting down, carrying screwed pins which are adjusted by means of nuts upon each side of the lugs, so that any required initial load may be put upon the spring. The spring is kept in its place by being passed through a narrow slot, wide enough to take the buckle at one side of the guides, and through another sufficient in width for the plates at the other; the wider slot is then reduced to the width of the narrow one by a keep plate bolted on the guide, thus preventing the spring from rising up when the pressure comes upon it. The buckle slides in another slot at the centre as the curves are taken by the engine. The weight is applied through the medium of independent springs placed above, the centre of which bear upon slippers which slide in curved guides upon the top of the box, and of the same curvature as the radius of the box, the axle box sliding under the shoes as it moves. F is a half cross elevation of this form of axle box. G shows another radial axle box, which has a much less length of radius than the former one, and has a side controlling gear of coiled springs arranged above the axle. A projection above, in the centre of the axle box, which also takes both bearings, has a spring upon each side of it, and two lugs reach down from a frame-stay of the engine and hold the bolt upon which the springs are placed, and also take their thrust. The bearing springs are on top and the pins slide in shoes as before. The advantage the Bissel bogie has over the radial axle box is easier action and. less friction, as the swing links offer much less resistance tban the curved guides and bearing