The Locomotive Of Today

The Engine : Connecting Rod Ends. 79 from ri to 1-3 times the area of the piston rod, andthe length of the rod, between the centres of pins at either end, should be from 2^- to 3 times the stroke of the engine, although small engines often liave them shorter than this ; the longer the rod, however, the smoother the engine will run. Fig. 16 shows several forms of rod ends. At A a rod having a “ strapped” big end and “solid eyed” small end is shown. The jaws of the strap fit over the two half brasses, and on to the end of the rod, being held by two tapering bolts, fitting accurately into holes, and secured by two nuts with a small cotter below; the two brasses encircle the crank pin, and are held together to the necessary tightness by a long, flat, tapering cotter, a push plate being inserted between the cotter and front brass; the cotter is prevented from slacking by means of two set bolts in the strap above and below the rod end, and a small cotter through its lower end. I he oil cup is forged solid with the strap, and machined to proper shape; the brasses each have two hollows into which melted L>abbit metal is pourecl, so as to reduce friction. The rod end has a large hole cut through it to reduce the weight. The small end is a part of the rod proper, and is bored out and fitted with a bush, which is prevented from turning by the insertion of a key. An oil hole and hollow are provided on the upper side to admit oil fed from a cup on the side of the crosshead. The rod, strap and bolts are of the best Yorkshire iron, and are machined all over. The cotter, push-plate, and small end bush key are of Steel, the “ brasses and small end bush being of gun metal. At B another small end, also solid eyed, but provided with means for adjusting and neutralising wear, is shown. It has two brasses and a wedge, which can be raised or lowered, this being done by means of a screwed bolt having a hexagonal head below, and which is prevented from turning, when set, by a locking plate placed over it, and held up by a split pin. The screw is held by a pin passin g through the rod end, and engaging in a groove in the screw. It is, however, doubtful whether any corresponding advantage is gained for the extra expense incurred in fitting up this adjusting gear, as the solid bush is much cheaper, and can be easily renewed when wear takes place. The rod shown at C also has a strapped big end, but the means employed for holding it to the rod are different: instead of the two bolts one cotter is used, and the rod end formed with recesses, under which the ends of the strap are held ; the two brasses, as before, are retained by a long cotter, checked by two set screws, and a small key below, and instead of the