LT4573B - Method of separating the seed mixture with the same physical properties - Google Patents

Abstract

This seed mixture of similar physical properties separation method is designed for agriculture, namely seed sorting technology, using an electric field. Sorting the mixture of different seed cultures with almost the same size and characteristics is a problem. This method offers to use as a separation the slightest differences of physical properties of the seeds thus revealed. The point of the method is that by using an electric field to affect the seed flow, seeds are overspread on a coarse fabric surface with a roughness 1-2 points higher compared to a surface of the seed mixture. The parameters of the electric field and its speed of movement are chosen according to the theoretic seed breakaway angle. The specific sizes of separation limits are determined by performed testing.

Description

The invention relates to seed sorting technology based on their frictional properties because simpler methods, such as seed size, aerodynamic, density distribution, are ineffective.

Known method for seeding is described in patent FR 2 299 095.

In this machine, the seeds are spread on a moving sloping cloth surface, whereby one species descends due to low friction with the surface and the other, due to its properties, lags behind the former and is carried away from the moving surface. For efficient sorting of the mixture, the seed friction angles with the surface must be at least twice as large (best for a mixture of round and flat seeds).

The description of patent RU 205417 discloses a device for seed sorting using differences in frictional and electrical properties.

The seed mixture is applied to a moving sloping webbing in the corona discharge field. The seed flow is pressed against a sloping surface not only by its mass but also by an electric field. Better squeezing of the seeds on a sloping surface allows for more efficient sorting by increasing the tilt angle and conveyor speed. This method is more suitable for the separation of seeds of the same type as inferior by weight and is ineffective for seeds of almost the same size in different cultures, for example the mother-clover mixture.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an effective separation of a seed mixture having similar physical properties.

This problem is solved by the method according to General Claim 1, in which, by using an electric field to affect the moving seed flow, the seed bearing surface is annular and 1 to 2 points higher than the seed of the mixture. parameters according to the dependence a- φ- arcsin ([K _a - K _o ) sin φ), where: a is the angle of tear of the seed from the transporter belt; φ - angle of friction, degrees;

Co R

R _a = kinematic parameter dependent on the conveyor drum

S radius and angular velocity; ω - angular velocity, rad;

R is the radius of the drum, m;

g is the acceleration of the free fall, m / s ^{1 2} .

K _o is the ratio of electrical to gravity.

This enables you to highlight the differences in surface characteristics and use it for sorting efficiency.

The proposed method of separating a seed mixture with similar physical properties is illustrated by an example and graphs showing:

FIG. - dependence of seed peel angle on material of conveyor belt;

FIG. - dependence of seed peel angle on voltage at potential electrode;

FIG. - dependence of seed release angle on the angular velocity of the belt in the separation zone.

An example. Seed mixture with a diameter of components of 1,510 ' ^{3 * *} m and a mass of 2-10' ⁶ kg consisting of rapeseed (surface characteristic 1 point) and impurities: pigeon (1-2 points), mustard (2-3 points) ) and a sticky lipo (4 points) is applied in a single layer to a moving cloth, such as a combed cotton, and applied to the corona discharge field. By successively varying the surface material of the conveyor belt, the voltage on the potential electrode for each material, and the angular velocity of the belt in the separation zone, specific limit values are obtained and curves are drawn to confirm the result of the invention.

FIG. 1 continuous curves: 1 - rapeseed, 2 - dove, 3 - mustard, 4 - sticky lip show how the tearing angles of all components of a mixture are different for a different material band when there is no voltage on the potential electrode. Key ₃ EN 4573 B and cultural weed atsiplėšimo angles differs very little and almost independent of the conveyor belt material. With a voltage of U = 20 kV, the difference in tearing angles becomes very marked, as shown in FIG. 1 dashed curves of analogous cultures 1, 2, 3, 4. The greatest difference in tearing angles was obtained with the spiky cotton webbing.

FIG. 2 curves: 1 - rapeseed, 2 - pigeon, 3 - mustard, 4 - sticky lip allow to determine the optimum voltage range of 20 - 30 kV, which gives the maximum difference of tearing angle (23 - 35 °) between cultures with similar properties.

FIG. 3 shows the dependence of the tearing angle on the angular velocity of the bar. In the absence of voltage on the potential electrode (continuous curves 1 - rape, 2 - dove, 3 mustard, 4 - sticky lip), the difference in tearing angles is almost independent of the angular velocity. Increasing the voltage up to 20 kV (dashed curves of 1,2,3,4 analogous cultures) significantly increases the difference between the different seed release angles.

The tests carried out have determined the specific parameters of the separation method of the seed mixture with similar physical properties and confirmed the possibility of effective separation in comparison with the known methods.

Claims (1)

DEFINITION OF INVENTION A method of separating a seed mixture having similar physical properties by feeding the mixture into a corona discharge field and distributing the seeds according to a friction angle with a moving surface, characterized in that the seed mixture is applied in a single layer on a moving cloth surface having a roughness of 1-2 with the seed surface of the mixture, expresses the electric field parameters and the velocity of movement in terms of the seed release angle and selects for the particular mixture according to the dependence: a = φ - arcsin (YK _a - K „) sin φ}, where: a - angle of tear of seeds from the transporter belt, in degrees; φ - angle of friction, degrees; g - kinematic parameter dependent on conveyor drum radius and angular velocity; ω - angular velocity, rad; R - radius of the drum, m; g - acceleration of free fall, m / s ² . K _o is the ratio of electrical to gravity. Method according to claim 1, characterized in that the voltage on the potential electrode 20 is maintained between 20 and 30 kV and the distance between it and the conveyor belt is 0.1 to 0.15 m. 3. A method according to claim 1.2, characterized in that the conveyor belt angular velocity in the separation zone is 4.25 - 5 rad.