SU1697903A2 - Screen - Google Patents

Abstract

This invention relates to the separation of granular bulk materials by size. The goal is to improve the quality of separation of seed mixtures. The sieve consists of a sheet screening surface (PP) 1 and a frame. An additional frame 8 with strings (C) 9 is installed at the corners of the frame. Gaskets 6 are installed between the frame and additional frame 8 on the supply side of the source material at PP 1 with a height smaller than the smallest thickness of seeds being processed. From the gathering side of the separated material with PP 1, gaskets 7 are installed, the height of which is chosen to be somewhat smaller than the width of the seeds of the material being processed. On PP 1 parallel rows of holes are made with rectangular holes with longitudinal and transverse bridges. In the middle part of the frame 8 there is an orientator 10 in the form of a U-shaped bracket. On the underside of the bracket, elastic elements 12 are fixed vertically above C 9 with a step equal to twice the C 9 installation step, and their thickness a does not exceed the width in C 9. The execution of the elastic elements 12 eliminates damage to the seeds that, when the elements pass by 12 are pinched between the edges of the openings of PP 1 and C 9. The orientators 10 above the C 9 strings exclude the movement of particles into the similar fraction along C 9, not touching PP 1. 3 Il.

Description

This invention relates to a technique for separating granular bulk materials by size.

The aim of the invention is to improve the quality of separation of the seed parts.

FIG. 1 shows a structural diagram of the sieve, top view; in fig. 2 - the same, side view; FIG. 3 is a section A-A in FIG. 2

The sieve consists of a sheet screening surface 1, on which rectangular holes 2 with longitudinal and transverse bridges 3 are made in parallel rows, and frame 4. At the corners of the frame 4

With the help of adjusting screws5 and gaskets 6, 7, an additional frame with strings 9 is installed. Gaskets 6 are installed between frame 4 and additional frame 8 on the supply side of the source material to the sifting surface 1, and their heights are chosen to be somewhat smaller than the smallest thickness of seeds being processed. This eliminates the jamming of the incoming particles between the screening surface 1 and the strings 9. The height of the gaskets 7, installed with the side of the gathering of the material to be separated from the screening

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surface 1, is chosen somewhat smaller width of the seeds of the material being processed. The heights of the pads G and 7 are selected for each seed mixture and they determine the installation of the additional frame 8 with an inclination to the screening surface

1 (with a rise in the direction of movement of the material on the screening surface

one).

The strings 9 are fixed on the additional frame 8 above the longitudinal bridges 3 of the screening surface 1. In the middle part of the additional frame there is an orientator 10 installed. It is made in the form of a different bracket 11, on the lower side of which there are elastic elements 12, the design of the elements 12 is elastic (capable of deviate from the vertical) eliminates damage to the seeds, which at the time of passing by the elements 12 are clamped between the edges of the holes

2 and strings 9. To reduce the permeability of elements 12 to particles (particle deceleration), which one side rests on the screening surface 1, and the second on strings 9, elements 12 are located vertically above strings 9 with a step equal to twice the pitch of string installation, and their thickness a does not exceed the width in strings 9 (condition a b must be maintained).

The sieve preparation for work consists in selecting the height of the gaskets 6 and 7 (their height is determined on the basis of examining the width of the seeds of the material being processed) and securing the additional frame 8 with the orientator 10 on the frame 4. When assembled, the sieve is installed in the grate mill of the standard cleaning machines.

The main part of the source material from the loading device of the grain cleaning machine arrives at the beginning of the screening surface 1 and under the action of oscillations of the machine’s sieve mill moves along the screening surface 1. The strings 9 orient the seeds along the holes 2 (the seeds move as if

along the stream formed by the bottom of a number of holes 2 and strings 9 on both sides), the seed mixtures are separated into two fractions by development in seed thickness: feedthrough - seeds, thickness less than or equal to the width of holes 2 of the screening surface 1, and descendent - seeds in size larger than the width of the holes 2. Part of the source material comes

from the loading device onto the sieve in such a way that their longitudinal axis is perpendicular to the direction of movement, which means perpendicular to the strings 9. Some of these seeds, especially those with

the length considerably exceeds the distance between adjacent strings 9, hangs on the strings 9 (position I, fig. 3) and does not fall on the screening surface 1, but slides along the strings 9. In the middle part of the sieve,

when part of the seeds have already sifted through the holes, the seeds hanging on the strings 9 are one side resting against the elastic elements 12 of the orientator 10 (since the elements 12 are mounted through one string 9,

and not over each). This side of the seed is slowed down, and the second, continuing to move, turns around element 12, and the particle, oriented along the strings-9, enters the screening surface 1, where

there is a separation in thickness (position II in Fig. 3).

Thus, the installation above the strings 9 of the orientator 10 eliminates the movement of particles in the gathering fraction along the strings 9, not

touching the screening surface 1, which significantly improves the quality of separation of seed mixtures.

Claims (1)

Sieve of invention above the strings, with a step equal to twice the pitch of the strings. and (ABOUT -J with about Lj 0 h I Aa four