THRESHING MACHINES. Threshers (colloquially "separators," because of the added duty of removing straw, chaff, and, to a great extent, grass seeds, weed seeds, and kernels of grain different in kind from the crop threshed) have remained for many years unchanged in main principles, but have far greater capacity and efficiency than formerly, and have some novel features added.
Fig. 1 is a representative improved American thresher and supplemental high stacker, made by Russell & Co., shown ready for work, the machine here represented traveling on the road by the locomotive power of the farm steam-engine used to furnish power when thresh ing. Specialist threshermen thus move the outfit from farm to farm, and thresh under con tract for a fixed charge per bushel. For the interior arrangement of the same thresher see Fig. 2. It has, just beyond the threshing cylinder. a novel distributing "beater," consisting of a central tube with radial flanges arranged in spirals reversed from the middle cir cumference of the tube toward either end (Fig. 8). As the beater revolves, the central beaks of the flanges strike into the flying mass shot from the cylinder and distribute it the full width of the machine. The prominence of the flanges is so modified as they approach the sides of the machine as to equalize distribution and cause immediate separation to begin. This spiral beater is supplemented by the ordinary four-winged beater to whip the straw open, from which the mass of straw and grain falls upon the picker table, and then upon a series of lifting fingers to lightly toss it with a fan-like motion, imparted by rock shafts. The throw of the fingers is adjustable to suit the condition of the material threshed. Beyond these fingers is a series of connected alternating open pickers, with a tedder action, passing the straw onward while the kernels drop between them. Over the picker tail the straw falls 15 in. upon the extension table, which has a vertical motion at the first or lower end, and a vibrating motion at the other end, raising the straw on saw-tooth edges, but urging the grain kernels in, backward, down its inclined floor. Meanwhile a drag-up chain-elevator-way captures and returns to the threshing cylinder, up along the outside of machine. any incompletely threshed ears, to be rethreshed. To improve the cylinder spikes
and enable them to stand the work of the high-speed machines of the day, a steel poll is welded upon a basis of tough iron (Fig. 4), greatly increasing the wearing quality of the tip of the spike without rendering its shank liable to snap. A stacker propels the straw and chaff up the incline of its floor by traveling slats of wood with their ends secured to a pair of moving belts. The stacker, though driven by belt from the thresher, is mounted independently on its carriage, and can be folded for transport (Fig. 5). In operation it swings slowly from side to side on a pivot on its carriage. by a self-reversing gear, and forms a lunette-shaped stack (Fig. 0). The delivery end of the stacker can be raised gradually, as the stack grows, by means of a cross-shaft, central under the car riage, engaging an upright screw at each end.
The driving power from the thresher can be diverted by a shifter-lever to actuate either the raising screws or the conveyor. To maintain a uniform delivery distance, and build the stack plumb, it is necessary for the outer end of the stacker to rise vertically. and this is accom plished by a link movement of the two posts supporting the heel of the stacker, which is designed to deliver straw up to as high as 23 ft. above ground level.
The Pitts (Buffalo, N. Y.) thresher has the right-and-left, spirally-flanged, transverse re volving distributor marked D. in Fig. 7. The card rack (above and beyond the ordinary beater, here marked C) stops access of straw to the distributor, but permits the large proportion of hulled kernels always shot over the beater by the whirling cylinder to fall into the distributor and be moved by it at once along an iron trough, B, to either side of the machine, and drop upon the grain-belt cells, where they are sure to be unoccupied by straw and chaff. This portion of the grain, always a large part, is, therefore preserved separate, instead of needlessly mingling with straw only to be sifted from it.