Characteristic Analysis of Oscillatory Vibrator in Elliptical Motion at Thresher Screening = Characteristic Analysis of Oscillatory Vibrator in Elliptical Motion at Thresher Screening

다국어 초록 (Multilingual Abstract)

As a screening device used for sorting grains, a swinging body of a four-bar link structure is mainly used. The motions of the swinging body are linear or elliptical. For linear motion, kinematic index (Kv) and the maximum horizontal velocity of the oscillator are used to calculate the mean transport velocity of the grain. However, in the case of elliptical motion, it is very difficult to utilize the values because the locus and velocity are different in depending on the positions on the the oscillator. Therefore, in this paper, the Kv values and the maximum moving velocity of the horizontal component according to the locations on the elliptical oscillator are calculated by computer. And the theoretical grain transport velocities are calculated using the grain mean transport velocity formula applied to the linear motion. In order to obtain the actual grain transport velocity, the perilla seed transport velocity at six points on the sieve were measured by a highspeed camera and compared with the theoretical value. Also, the grain transport velocity according to the projection angle, major & minor axis of elliptical motion, the rotating direction, and frequency was investigated. The four - bar linkage used in the experiment has a 1.8cm eccentrical driving unit and a rotatable slider at the follower unit. The cereals used in the experiments were perilla grain and the experimental results were generally in agreement with the theoretical values.