RU2457047C1 - Method of loose material separation by air and device to this end - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to agricultural machinery, particularly, to grain separators. Proposed method comprises feeding initial material, separating light-weight dirt by airflow and material fractions along and against airflow. Grain is fed into air channel and blown by vertical airflow from bottom to top. Said airflow is divided into flat air jets to produce low- and high-air speed blowing zones with speeds higher and lower than that of full-value grain hovering. Proposed device comprises grain feeder, air separation channel and airflow splitter. Expansion chamber with guide plates is arranged upstream of grain feed into air channel while airflow splitter is arranged downstream thereof. Airflow splitter is made up of vertically displacing vanes that allow their independent control to make channels there between and aforesaid blowing zones.

EFFECT: higher quality of separation.

2 cl, 1 dwg

Description

The invention relates to agricultural machinery and, in particular, to grain cleaning machines for cleaning and sorting seeds of various crops.

A known method of separating bulk materials during pneumatic transportation (AS No. 458341, MKI V07B 7/02), comprising separating the transporting air from the material, changing the direction of movement of the latter with a domed distribution using a reflector, subsequent purging of the material with air and air exhaust with small particles in the precipitant. The material transported by air is rotated relative to the direction of transportation, and the subsequent purging of the material is carried out by additional circulating air introduced in a tangentially dome-shaped distributed material.

The disadvantages of this method include the inability to ensure high efficiency of the separation of the material during its rotation relative to the direction of transportation in rectangular pneumatic channels and with their considerable length, which is the case in modern grain cleaning machines. The centrifugal force arising from the rotation of the particles of the material will be unstable and will seal the moving flow of the material and thereby reduce the efficiency of its separation.

Closest to the invention in technical essence and the achieved result is a method of air separation of grain materials (AS No. 977069, MKI V07V 7/00). According to this method, the separation of the material by the air flow into fractions and the withdrawal of fractions in the direction and perpendicular to the direction of the air flow is carried out using twisting of the grain material before separation of the air flow.

The disadvantage of this method is the low separation efficiency, the twisting of the grain material before entering it into the pneumatic channel does not contribute to the stable orientation of the grains. Centrifugal forces will simultaneously both contribute to and inhibit and mix the grain material, and as a result, the process will be probabilistic and impossible at modern grain cleaning machines.

A device for separating mixtures of air flow (AS No. 387751, MKI V07V 7/00), including a grain mass accelerator, an air flow source, an air channel and dividers installed in the air channel.

The disadvantages of this device include: the relatively short length of the path of movement of the grain mixture above the divider, which is limited by the width of the air channel and is about 20 cm. This path the grain mixture passes with the help of an accelerator at a certain speed of 10 m / s and crosses the air flow at an angle of 90 ° moving at a speed of several tens of meters per second. At the same time, the air flow rate is several times higher than the rate of rotation of the grain part of the mixture, which does not exclude the removal of grain into waste. Due to the short-term interaction of air with the grain mixture, it does not have time to loosen, which leads to a decrease in the separation efficiency.

The technical result of the claimed invention is to improve the quality of separation of grain materials.

The specified technical result is achieved by the fact that in the method of pneumatic separation of grain materials, including the supply of materials, the selection of lightweight fractions by the air flow and the withdrawal of fractions in the direction and against the direction of the air flow, the grain material is fed into the pneumatic channel and blown from the bottom up by a vertical air flow divided into contact between flat air jets with the formation of successively purging zones of high and low air speeds in the range of more and less speeds full grain, as well as the specified technical result is achieved by the fact that in the device for pneumatic separation of grain materials, including a grain feeder, pneumatic separation channel and an air flow divider installed in it, an expansion chamber with guide plates is located above the path of input of grain material into the pneumatic channel, and below - air flow divider made in the form of blades with the possibility of vertical movement and independent regulation relative to each other with the formation m mezhlopastnyh channels sequentially and zones of high and low speed mode exiting air jets.

The drawing shows a structural and technological diagram of a pneumatic separator of grain materials according to the proposed method.

The device includes a pneumatic separating channel 1, in which there is a window 2 for feeding grain material from the hopper 3. Below the window for entering grain material into the pneumatic channel, an air flow divider 4 is installed with the possibility of vertical movement and including blades 5 with the possibility of rotation relative to the vertical position. The blades divide the outgoing air stream into zones I and II when it leaves the divider. Above the window for feeding the grain material, there is an expansion chamber 6 and then a precipitation chamber 7 for lightweight impurities. At the bottom of the pneumatic channel, a clean grain receiver 8 is located, and guide plates 9 are mounted in the expansion chamber.

The device operates according to the proposed method as follows.

The mixture of grain and impurities from the hopper 3 through the window 2 enters the pneumatic channel 1. The air drawn in by the fan (not shown) through the clean grain receiver 8, the inter-blade spaces of the blades 5 of the divider 4 enters the expansion chamber 6 and then into the precipitation chamber 7 and through a fan into the atmosphere.

In addition, air enters the pneumatic channel 1 through the window 2 of the hopper 3 together with the grain mixture and is distributed over the divider 4 along a certain path. In zone I, the air velocity is higher than the speed of the benign grain soaring, and it rises up into the expansion chamber 6, where the air velocity decreases and under the action of the guide plates 9, the grain mixture moves to the middle part of the expansion chamber and begins to settle in zone II and further into the clean grain receiver.

Intensive mixing of the grain mixture takes place in the expansion chamber, which contributes to the effective removal of lightweight particles into the settling chamber 7. The air regime in the inter-blade channels of the divider and the expansion chamber is regulated by the position of the blades and the divider.

Claims (2)

1. The method of pneumatic separation of grain materials, including the supply of material, the allocation of lightweight impurities by air flow and the withdrawal of fractions in the direction and against the direction of the air flow,
characterized in that the grain material is fed into the pneumatic channel and blown from the bottom up by a vertical air flow divided into flat air jets that are in contact with each other to form sequentially purging zones of high and low air speeds in the range of more and less full grain speed. 2. A device for pneumatic separation of grain materials, including a grain feeder, pneumatic separation channel and an air flow divider installed in it, characterized in that an expansion chamber with guide plates is located above the path of input of grain material into the pneumatic channel, and an air flow divider made in the form of blades is located below with the possibility of vertical movement and independent regulation relative to each other with the formation of inter-blade channels and sequentially zones of high and low high speed regime of the outgoing air jets.

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