The ordinary grain cleaner is imperfect in one essential point, viz., the feeding of the grain. The invention we are about to describe is designed to remedy this defect, and consists in delivering the seeds or grain to the blasts by the centrifugal action of a revolving disk plate placed in the wind trunk, so that the seeds or grains shall be thrown out horizontally in a thin sheet across the blast, and the unbroken ascending current take the lighter grains immediately from the heavier ones, and thus separate them. In our illustration, which is a vertical longitudinal section through the invention, A is the outside case. The fan, b, is rotated by a crank and gear wheel, and moves in the direction of the arrow, I, so as to draw a current of air through the machine, and force it out at D. The fan blower runs in a case, E, which is closed except at the eyes, F, the air passing from the machine through side ducts, and throujrh F into the fan box. H is a vertical wind flue, open at its lower end, but closed at the top. Through the center of this wind flue there passes a feeding tube, I, which rests by its flanges, c, on the top of H, and by means of set screws, d, this tube can be raised or lowered in H, to regulate the feeding J in of the grain, and in its upper end is placed a hopper, J, in which the seed or grain is placed. Two bridge trees, K L, form bearings for a shaft, e, that passes through I, and this shaft has on its upper end a bevel wheel, /, which is rotated by the bevel, g, on the shaft, h, moved by the band, i, and band wheel, M, from the wheel, N, on the crank' axle. Near the bottom of e there is placed upon it the disk cup, 0, which may be termed a " distributor." This being rapidly rotated throws the grain off by its centrifugal force, the fed in, in the ordinary way, but the separation of the light from the heavier products takes place when the grain or seeds are thrown across the blast, there being a momentary cessation of motion as the momentum of the grain thus thrown from the distributor gives way to the superior force of the ascending column of air, and whilst at this almost apparent state of rest, the heavier products fall, by their gravitation, and the lighter ones pass up with the blast, the strength of which may be regulated by slides. The hopper or feeding tube, I, should be kept full of grain, so that no air can pass through quantity being regulated by the set screws, d. The grain thus thrown off pass in a thin sheet across the current of air ascending through the wind trunk, the lighter particles or grains, as well as the impurities, being carried up with the blast, whilst the heavier grains fall through the trunk. By this throwing off horizontally across the blast the seeds or grains, the heavy grains do not strike and carry down with them the lighter ones, as is generally the case when they are the tube. The light grains pass through the opening, Q, into the box, and fall down upon S, from which they can be withdrawn by a gate m. A board, E, prevents any from passing into the fan box. The smut, chaff, dirt, c, pass through the fan box, and are discharged at D. The cylinder, , below the distributor, 0, is intended to prevent a counter current or eddy below the distributor—it being important that the ascending current should not be broken by any disturbing force. It was patented June 8, 1858, by the inventor, A. J. Vandegrift, of Lexington, Ky., who will give any further information.
This article was originally published with the title "Improved Grain Cleaner" in Scientific American 13, 45, 360 (July 1858)