GB840995A - Improvements in rotary separating mechanism for harvester threshers - Google Patents

Abstract

840,995. Screening apparatus. ALLIS-CHALMERS MANUFACTURING CO. May 22, 1958 [May 31, 1957], No. 16499/58. Class 117 [Also in Group I] A separating mechanism for a harvester thresher comprises a stationary concave sifting grate 18 within a housing 31, a rotary agitator 19 which advances threshed material over the grate from one end to the other end, whereby grain falls through the grate, and a side aperture at said other end for the discharge of straw from the housing, said aperture being associated with a beater element 54 radially offset from the agitator so as to engage the straw and eject it from that aperture. As shown, the separating mechanism forms part of a harvester thresher supplied with power from a power take-off shaft of the tractor which draws it. The thresher includes a header 7 and thresher mechanism 8 from which the threshed material is fed to one end of the housing 31. The agitator consists of a number of helical conveyer flights 89, 91 mounted on angle bars 84, 86 carried by and circumferentially spaced on discs extending from a central drive shaft 78 rotated in the. direction of the arrows, Figs. 3, 6 and 7. At the straw outlet end of the housing the agitator comprises paddles 93 extending radially of the angle bars and producing a rotation of the threshed material. Adjacent those paddles is arranged the beater element 54 located within a straw outlet hood 49 and comprising a rotary shaft 129 with pivotally mounted flail members 161 driven at a higher speed than the agitator. The grate comprises a number of spaced parallel bars 57 supported on curved angle iron girders such as 58 by clamps. A comb structure 162 comprising parallel spaced wires extends downwards from the upper part of the housing and extends the length of the threshing cylinder 9 and allows passage of grain therethrough to the space below the grate. Wire prongs 163 in the mid-section of the housing prevent material conglomerating during its movement towards the straw discharge end. As the threshed material is moved over the grate, grain, unthreshed heads and chaff fall through it to a grain drag 102, comprising a pair of spaced chains interconnected by transverse drag bars 106, and is carried thereby to a tray 98 and fed to an oscillated shoe 96 which, with the aid of a fan 108, produces a separation of the grain from the rest of the material. Clean grain is delivered by a feeder 156 to a shoot 157 and a bin 158, and the tailings are fed by a feeder 148 to a shoot 151. The rotary parts are driven from the power take-off shaft of the tractor via belt and chain gearing. Specification 734,642 is referred to.