RU2447942C2 - Centrifugal multistage grain crusher - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to agriculture. Proposed centrifugal crusher comprises composite cylindrical case 9 with loading bin 1 and discharge branch pipes, three crushing stages. Note here that successor stage features larger diameter than antecedent stage. Said three stages are arranged on vertical shaft 32, one above the other, in case 9. Grate shell rings and fan 16 are arranged around two top stages, Said fan 15 shares vertical shaft 32 with said three stages and is fitted under the last of them. Cleaning brushes 13 fitted on shaft 32 are arranged opposite said grate shell rings. Brushes 13 are made from kapron fibers and shaped to grate shell ring inner surface contour.

EFFECT: intensified sieving.

2 cl, 1 dwg

Description

The invention relates to devices for crushing materials, namely to centrifugal multistage crushers for grinding feed grain for fodder for livestock and poultry.

Mostly the invention can be used on livestock, poultry farms and complexes, in the feed and flour milling industries.

In addition, it can find application in the chemical, pharmaceutical and other industries.

Already known device for grinding materials described in A. with. No. 856546, M.cl. 3 VOS С13 / 14 1981, USSR under the name "Hammer Crusher".

This device contains a step-down housing expanding downward, inside of which a rotor with hammers is mounted on a vertical shaft, the rotor shaft is equipped with blades that are installed at an acute angle to its horizontal axis and are located under the hammers.

The disadvantages of this device are the low productivity during grinding and the uneven particle size distribution of the resulting product.

These shortcomings are due to the fact that the finished product ground in the first stage is not removed from the grinding zone in a timely manner, but remains in it until all stages have passed. This leads to a decrease in productivity, an increase in the energy intensity of the grinding process and a decrease in the quality of the resulting product.

Another device is also known, described in patent No. 624588, M.cl. 3 02C 13/288, 1981, Switzerland, under the name "Impact mill for grain with ring sieve and fan."

This device comprises a detachable housing, loading and unloading devices, a horizontally located shaft on which the saw is mounted, a fixed ring sieve, a fan, an annular double intermediate partition.

The disadvantages of the known device are the uneven distribution of the source material in the grinding zone and the uneven fractional composition of the resulting product.

These shortcomings are due to the horizontal arrangement of the drive shaft, on which grinding beats are installed and single-stage grinding.

The closest in technical essence and the achieved technical solution is the device described in A.S. No. 122993 (USSR) 1986 under the name "Centrifugal multistage crusher for grain" and selected as a prototype.

This device contains a prefabricated cylindrical body with a loading hopper and discharge nozzles, three grinding stages installed on it on a vertical shaft one above the other, each subsequent grinding stage has a diameter larger than the previous one, sieve shells and an unloading winglet located around the upper two grinding stages are mounted on one shaft with working bodies under the last of them.

Compared with the above analogues, the prototype device has the advantage. Increases productivity during grinding by stabilizing the degree of grinding of feed grain, reduces the energy consumption of the grinding process due to the timely withdrawal of the finished product from the grinding zone.

At the same time, the prototype device has a drawback, during the grain grinding process, some particles that are not until the grain is crushed are stuck in the holes of the sieve shells, which complicates the exit of subsequent crushed particles through the holes of the sieve shells, this leads to a decrease in the living cross section of the sieve surface, thereby reducing throughput of sieve shells.

The aim of the present invention is to increase the throughput of sieve shells by cleaning the sieve surfaces of the shells in the process of grinding grain, from stuck in the holes of the sieves not to the crushed particles of grain derty.

This goal is achieved by the fact that the centrifugal multistage grain crusher is additionally equipped with a device for cleaning particles of cereal tar stuck in the holes of the sieve shells.

This device consists of two cleaning brushes made of nylon fiber, having a configuration along the contour of the inner surface of the sieve shells and mounted on a vertical shaft opposite the sieve shells, after the first and second grinding stages.

When the vertical shaft is rotated with two cleaning brushes installed on it, the holes of the sieve shells are cleaned by brushes of particles of grain debris stuck in them. This leads to an increase in throughput of sieve shells. This device is not known in the crushers in question.

Figure 1 schematically shows a centrifugal multistage crusher for grain (longitudinal section).

A centrifugal multistage grain crusher (Fig. 1) includes: a loading hopper 1, a prefabricated cylindrical body 9, to the lower and upper parts of which the lower 17 and upper 5 end plates are attached. Cases 18 and 33 of the rolling bearings of the vertical shaft 32 of the crusher, on which the hubs 10, 15 and 31 are mounted, are strengthened at the centers of the end plates. Disks 7, 12 and 29 are mounted on the hubs, forming rotors, the diameters of which increase sequentially from top to bottom in the direction of movement of the initial product . On the upper surface of each rotor, two rows of annular grooves are grooved along the periphery, into which replaceable working bodies 20, 23 and 27 of the rotors are installed, made in the form of trapezoidal rings with grooves that form fingers. Stators 28 are installed between the cylindrical assembly body 9. The stator role for the first grinding stage is performed by the upper end plate 5. An annular groove is made on the lower surface of each stator, into which replaceable working bodies 3, 11 and 14 of stators are installed, made in the form of trapezoidal rings with grooves forming fingers. The annular groove of the stators is machined so that when the working bodies 3, 11 and 14 are installed in it, the latter are located between two rows of working bodies 20, 23 and 27 of the rotors, thereby forming a grinding stage. The role of fender decks 25 is performed by interchangeable sieves with different hole diameters, made in the form of an annular thick-walled sieve with cone-shaped openings, providing a given value of the passage particle of the crushed product. The taper of the hole of the sieve matrix prevents it from partially clogging with crushed grain during operation. Matrix sieves are mounted against the first and second grinding stages to the lower surface of the stators. Cone funnels 26 play the role of interchangeable sieves with different hole diameters, for timely withdrawal of the crushed finished product from the grinding zone and at the same time play the role of pitched boards to guide grain particles not shredded to the next grinding stage, therefore, the cone funnel 26 is sieve in the upper part, and in the bottom is solid. Sieve matrices and cone funnels form a removable sieve shell. In the process of grinding grain, some particles that are not thoroughly crushed grain are stuck in the holes of the sieve shells, which leads to a decrease in the living cross-section of the sieves, thereby reducing the throughput of the sieve shells.

Two cleaning brushes 13 are installed on the vertical shaft 32 to clean the sieve shells from the particles of grain debris stuck in them 13. The cleaning brushes are made of nylon fiber, have a configuration along the contour of the inner surface of the sieve shells and are adjacent to the inner surface of the sieve shells with their working surface. The cleaning brushes 13 are mounted against the sieve shells to the vertical shaft 32 with the help of clamps 22, and when the brushes rotate the brush, the sieve surface of the shells is cleaned of particles of grain debris stuck in them. Pitched boards 24 are installed in the crusher space 6 of the crusher. The pitched boards are made in the form of a truncated cone with a smaller base to the top and are designed to direct the finished product through the discharge windows 8 of the stators to the branch pipes 30. The loading hopper 1 with control flaps 19 is installed above the loading windows 2, in the upper end plate 5. On the upper end plate 5 above the sieve space 6 of the crusher, adjustment windows 21 are provided concentrically around the circumference with jumpers, provided with an annular ring slonkoy 4 mounted in the annular groove. To create a vertical air flow in the sieve space 6 and to withdraw the finished product from the crusher inside the prefabricated cylindrical body 9, the winged valve 16 is installed on the vertical shaft 32. Moreover, the winged valve is installed under the lower grinding stage, the diameter of which is larger than the diameter of the lower grinding stage. The vertical shaft with three grinding stages is driven by an electric motor through a driven pulley 34 of a V-belt drive.

Centrifugal multistage crusher for grain works as follows. The fodder grain to be crushed from metal and extraneous impurities, which is to be crushed, is loaded into the loading hopper 1 and through the loading windows 2 in the upper end plate 5, the opening value of which is regulated by the shutters 19, enters the rapidly rotating disk 7 of the first grinding stage. The material being crushed due to centrifugal force is discarded from the center of rotation to the periphery, where it is affected by the rapidly rotating working bodies 20 of the rotor and the stationary working bodies 3 of the stator. The main process of grinding feed grain is carried out using the method of grinding "chipping - slice" between the side faces of the working bodies of the rotor 20 and the side faces of the working bodies of the 3 stator. The initial product receives additional grinding by hitting the sieve matrix 25. Finished product at the first grinding stage to the desired particle size distribution is removed from the grinding zone through the sieve shell and sent to the next grinding stage. This is due to the vertical air flow formed in the sieve space 6 of the crusher, and due to the absolute speed of the air flow inside the crushing chamber. Those crushed particles of grain tart that are stuck in the holes of the sieve shell during sifting, using two cleaning brushes 13 rotating on a vertical shaft 32, adjacent to the inner surface of the sieve shell by their working surfaces, are removed from the holes of the sieve shell and sent to the next grinding stage . Next, the finished product on a ramp 24 through the discharge windows 8 enters krylach 16, which through the discharge pipes 30 lead him out of the crusher. The grinding process in the subsequent stages of grinding is similar to the grinding process in the first stage of grinding.

Thus, an increase in the throughput of the sieve shells due to the cleaning of the sieve surface with the help of the installed brushes ensures timely removal of the finished product particles crushed to the required particle size distribution from the grinding zone, which leads to an intensification of the process of sieving the crushed particles through the sieve shells.

Claims (2)

1. A centrifugal multistage grain crusher, comprising a prefabricated cylindrical body with a loading hopper and discharge nozzles, three grinding stages mounted on it on a vertical shaft one below the other, each subsequent one having a diameter larger than the previous one, sieve shells located around the upper two grinding stages and krylach installed on one vertical shaft with three grinding steps under the last of them, characterized in that on the vertical shaft opposite to the sieve shells Lena cleaning brush made of nylon fibers and having a configuration of the contour of the inner surface of the sieve mantle. 2. The crusher according to claim 1, characterized in that the working surface of the cleaning brushes is in contact with the inner surface of the sieve shells.