SU975093A1 - Apparatus for cleaning and sorting grain - Google Patents

Description

The invention relates to electrical separation of bulk materials and can be used in agriculture.

A device for cleaning loose mixtures is known, comprising a conveyor for moving the mixture, an electrode mounted above the conveyor, and an additional conveyor for removing impurities 1.

A disadvantage of the known device is the low efficiency of the separation process.

The closest to the proposed technical essence and the achieved result is a device for cleaning and sorting of grain, containing a feed hopper, a main conveyor with an endless grounded canvas, placed above it an additional conveyor with an electrode connected to a high voltage source, and receivers of separation products G2 .

The disadvantage of this device is the low efficiency of the process of separation of multicomponent mixtures.

The purpose of the invention is to increase the efficiency. the efficiency of the separation of multicomponent mixtures.

This goal is achieved by the fact that the additional conveyor is made in the form of discs of electrically conductive material, mounted parallel to the main conveyor parallel to rotation, and the disks have a dielectric coating on the lower plane.

In this case, the lower part of the dielectric coating of the disks is made of an elastic material, and the receivers of separation products are provided with metal guides by troughs connected to a high voltage source.

FIG. 1 and 2 show the structure of a device for cleaning and sorting grain; in fig. 3 - the design of one of the discs with the same forehead.

A device for cleaning and sorting grain consists of a feed bin 1 with grain 2 located above an endless electrically conductive tape.

25 3 main conveyors, which are tensioned on two leading grounded metal rollers 4. Above the conveyor belt there are disks 5 and 6, the planes of which are parallel to the surface of the conveyor belt, and the axis of rotation are perpendicular to its plane. On the opposite side of the conveyor belt, metal guides 7 and 8 are located under the disks. The ends of the channels are located above the receiving bins 9 and 10. Electrode disks are connected to high voltage sources 11 and 12. Under the end of the conveyor, opposite to that above which the feed hopper 1 is located, there is a hopper 13.

Each disk of the auxiliary conveyor consists of a metal part 14 connected to a high voltage source 11, one of the output terminals of which is grounded. Under the metal part 14 there is a dielectric coating consisting of a non-hygroscopic dielectric 15 and a flexible dielectric 16 located at the bottom, for example, foam rubber. An additional high voltage source 17 is connected to the output terminal of the high voltage source 11, the second terminal of which is connected to the metal trough electrode 7.

The design and wiring diagrams for all drives are the same.

A device for cleaning and sorting grain works as follows.

As a result of the rotation of the driving rollers 4, the belt 3 moves in the direction from the feed hopper 1 to the receiving hopper 13. On the tape 3, feeds a mixture of grain from the feed hopper 1 and moves on the main conveyor belt to the disks 5 and b of the additional conveyor.

Since the metal parts 14 of the discs are connected to high voltage sources, and the conveyor belt is at zero ground potential, an electric field with a strength E, is created between the disc and the main conveyor belt. The lightest elements of the mixture, under the action of the floor, receiving a charge from the belt 3 of the main conveyor, begin to take off towards the disks 5 or 6. As the experiments show, the particles move with acceleration. Their speed is maximum at the moment of impact with the dielectric, which most often results in the crushing and departure of grain from the electrical system. To eliminate this phenomenon, a layer of elastic dielectric 16, such as foam rubber, is placed under a layer of solid dielectric 15.

With the passage of grain on the conveyor belt 3 under the electrode disc, particles and grains, the weight of which is less than the strength of the electric field acting on them, fly up to the upper disk. Those grains whose weight is greater than the electric floor acting on them,

move further on the conveyor belt 3. The flying-up grains are braked by an elastic dielectric, go into it and stop. These grains 18 are held on this dielectric by the force of the attraction of the charged grain to the metal electrode 14, since the charge cannot be drained from the grain or neutralized due to the dielectric coating. Due to the rotation of the electrode disk 5, the grains adhered to it move from the region above the conveyor belt to the region above the grooves (Fig. 2, arc arrow). The potential of the chute 7 is higher than the potential of the metal disk 14. The magnitude of the output voltage of the additional source 17. There is an electric field E between the drive and the disk E, the intensity of which is determined by the output voltage of the additional source 17 and with respect to the metal disk 14, this field is opposite to field E ,. When the grain on the upper disk approaches the chute, a force starts to act on it from the upper disk downwards. This force and force of gravity cause the separation of the grain or particle from the lower surface of the disk and its fall into the chute 7. Moving down this chute, the grain falls into the corresponding receiving bin 9.

The grains, not attracted to the first disk 5, move along with the conveyor belt further and fall under the second disk 6, which is connected to a high voltage source, the output voltage of which is higher than that of the previous one. As a result, the tension between the second disk B and tape 3 is higher than between the disk and tape.

The next fraction of grains, the weight of which is less than the field force acting on them, is attracted by the second disk and is sent to the next receiving bin 10. There may be several such disks. Each of them will produce the appropriate fraction. Grains and portions of 1da, not touched to any disk, fall into the receiving bunker 13.

Thus, the implementation of an additional conveyor in the form of dielectric coated discs, the execution of the lower part of the dielectric coating of elastic dielectric disks and the presence of metal guide grooves make it possible to increase the efficiency of the separation process of multicomponent mixtures.

Claims (3)

1. A device for cleaning and sorting grain, containing a feed bunker, a main conveyor with endless grounded blades, an additional conveyor placed above it with an electrode connected to a high voltage source, and receivers of separation products, such that in order to increase the efficiency of the process of separation of multicomponent mixtures, the additional conveyor is made in the form of Discs of electrically conductive material, installed parallel to the main conveyor belt with the possibility of rotating The discs have a dielectric coating on the bottom plane. 2. The device according to claim 1, which is based on the fact that, in order to Eliminating seed pitch from an additional transporter, the lower part of the dielectric coating of the disks is made of an elastic material. 3. A device according to claim 1, characterized in that the receivers of the separation products are provided with metal guide grooves connected to a high voltage source. Sources of information taken into account in the examination 1. USSR author's certificate No. 222791, cl. OZ S 7/08, 1967, 2. USSR author's certificate 378251, cl. At 03 C 7/08, 1971 (prototype).