This paper is results of the experimental study on screening rate and flowing velocity of paddy particles on the screen under the reciprocating motion. The four-bar linkages is adopted for oscillating mechanism to make the screen act the reciprocating elliptical and circular motion. The main results are as follow ;
1) Larger amount of the frequency, amplitude and projection angle of screen, together, make the flowing velocity increase respectively.
2) The screening rate is increased with the increasing of the feeding rate of paddy. And the relationship between the screening rate and the feeding rate at the most suitable frequency is given by the following equation.
η = aQ^<-b>
η : screening rate (%)
Q : feeding rate (<cm>^3/sec)
a, b are constant respectively.
3) The most suitable frequency vary according to the amount of projection angle and the inclination angle of the screen for the level surface , but it is existed at the value of K = about 1-2.5, where K is Centrifugal effect.
4) Kv≦I shows that the paddy travel under the sliding motion, and Kv≧I is under the jumping and sliding motion together on the screen surface. And the most suitable frequency exist under Kv≦I or Kv≧I, on both. Where Kv is screening index.
5) In the practical use aiming at keeping the prevention of blinding, large durabillity and high capacity of screen, the flowing velocity is higher than above result.
On the case of this condition of the horizontal reciprocating screen the projection angle is the value of α = 35-45 (degree).