The lengths of the links comply with the conditions: A͞B=C͞B=B͞M=1, E͞A=0.305, C͞E=0.76, M͞D=0.66, F͞D=0.8, C͞F=1.66, E͞F=2.36 and β=114°. Point M of connecting rod 2 in four-bar linkage EABC describes a connecting-rod curve of which a portion approximates a circular arc with its centre at point D (this arc is not shown) and of a radius equal to D͞M(link 4). When point M is on this portion of its path, link 5 is almos t stationary, i.e. it practi ally has a dwell at its extreme position. At the extreme right-hand position of link 5, grain from hopper Q flows into trough T. Since the dwell of link 5 in this position corresponds to a half-revolution of crank 1, the grain has the opportunity to fill trough T. In the next half-revolution of crank 1, link 5 with trough T which is filled with grain makes one full oscillation. At this, the grain is scattered by the trough, the individual grains falling farther or nearer depending upon their size and mass. Link 7, actuated by link 5 through intermediate link 6, has a shutter which closes the output hole of hopper Q, opening it only during the dwell of link 5.
$802$LW,SF$