Mechanism of destruction of bunches of dried grapes by the comb separator of the vertical type
Аннотация
Abstract. The production of kishmish and raisins involves the process of crushing and cleaning dried grapes. This process is sufficiently studied, but it is always being improved. The lack of a small-sized mobile comb separator, acceptable for use at home, prompted the authors to develop a working hypothesis about the creation of a mobile such machine.\n\nIn this plan, a design of a comb separator with a vertical arrangement of the working shaft is proposed, on which dismembrators with rotating fingers will be installed on three levels. The principle of operation of the device is based on the impact of the processed product with the fingers. When determining some of the parametric characteristics of the comb separator, they based their judgments on the knowledge of the known laws of dynamics and kinematics. By analogy with the inelastic impact, the work of deformation of individual dried grapes is considered, in which they are not damaged and retain their shape. It is proved that the work of deformation increases in proportion to the square of the circumferential velocity of the fingers. A bunch of dried grapes, entering the space between the rotating fingers, interact with the grooved surface of the latter and are ground to individual berries and combs. It was experimentally proved that the degree of cleaning of grapes from the combs depends on the distance of the fingers from each other and their total number. For the experiment, the fingers were made in the form of a cone-shaped hollow nozzle, covered on the outside with a rubber cuff with spiral notches. The height of the finger h = 80 mm, the angle of taper φ = 20-25°, the number of them in the first row – 6 pcs, on the second – 12 pcs, and on the third – 18. The diameter of the disc of the dismembrator – 550 mm, the speed of rotation of the working shaft varied within the range of nв = 50-300 min-1 through the belt drive. The maximum linear velocity of dried grapes is υ=0.35-0.42 m/s at the humidity of the processed product W = 18-21%.