RU233096U1 - GRAIN GRINDING DEVICE - Google Patents

Abstract

Utility model object: device for grinding grain. Application area: agricultural engineering, where crushers are used, for example, in flour, cereals and feed production. The essence of the utility model: in a device for grinding grain, comprising a housing, a disk located in its cavity, in which wedge-shaped channels are made, expanding from the center to the periphery, a shaft, radially to which working elements in the form of thin rods are fixed, located in several rows, above which a feed hopper is installed, made in the form of two cones - an external and an internal one, turned by their bases to the disk, from which they are separated by a cylindrical mesh partition, which tightly covers the disk, as well as a fraction distributor, made in the form of a set of solid cones, which are stepwise expanded by their bases to the disk, the internal cone is made in the form of a set of separating cones with a brachistochronic surface, between which slotted holes are located, the number of which corresponds to the number of solid cones of the fraction distributor, and the size depends on the equivalent diameter of the separated particles. Technical result: the circulating load in the grinding chamber is reduced, the quality of the grinding process is improved and the energy intensity of the process is reduced.

Description

The utility model pertains to the processing industry, in particular to devices for grinding grain, and can be used in the grain processing industry and agriculture.

A device for grinding grain is known, comprising a frame with a loading hopper fixed to it, having a window for the grain outlet, a conical accelerating plate with ribs placed on the drive shaft, a sieve, a reflector and a drive [Patent of the Russian Federation No. 2534111 C1. IPC B02C 13/14, B02C 9/00. Device for grinding grain. Bulletin No. 33 of 11/27/2014].

The disadvantage of the known device for grinding grain is the insufficient degree of grinding of the product due to abrasion against the sieve, which leads to an increase in the energy intensity of the process.

Also known is a device for grinding grain, comprising a feed bin, a housing, a shaft located in its cavity with working elements in the form of rods, which are installed in a mesh shell with reflectors and separated from below by a disk partition with holes [Patent of the Russian Federation No. 2254165 C1. IPC B02C 13/14. Grinder - mixer. Bulletin No. 17 of 20.06.2005].

The disadvantage of the analogue is that during operation of the known device for grinding grain it is impossible to ensure a constant direct and uniform impact of the working element on the grains, which enter the working element in a continuous uncalibrated flow, which leads to uneven grinding of grain of different sizes, overgrinding of small grains and undergrinding of large ones, which need additional grinding. After feeding the grain into the grinding chamber, it mixes with the mass of the material that is being ground and is captured by the working elements in the form of rods in a circular motion. It is known that the speed of movement of particles of different sizes due to centrifugal and inertial forces is not the same, therefore large particles move faster than small ones. This leads to stratification of particles in the layer of the material being ground by size. Large particles end up on the surfaces of the mesh shell and the disk partition with holes, small ones - on the surface of the layer. With such an arrangement of particles in the layer, it is difficult for large particles to get under the blows of the rods. In addition, they close the openings of the mesh shell and the disk partition, which worsens the conditions for removing small particles from the grinding chamber. Small particles on the surface of the layer are constantly subjected to the impact of the rods and are over-ground. All this leads to an increase in the energy intensity of the process and unevenness of the fractional composition of the crushed particles.

The closest in its technical essence is a device for grinding grain, comprising a housing, a disk located in its cavity, in which wedge-shaped channels are made, expanding from the center to the periphery, a shaft, radially to which working elements in the form of thin rods are fixed, located in several rows, above which a feed hopper is installed, made in the form of two cones - an external and an internal one, turned by their bases towards the disk and from which they are separated by a cylindrical mesh partition that tightly covers the disk, as well as a fraction distributor made in the form of a set of solid cones, which are steppedly expanded by their bases towards the disk [Patent of Ukraine No. 95435 C2. IPC A23N 5/00, B02C 13/00. Device for peeling and grinding grain. Bulletin No. 14 dated 25.07.2011].

When operating the known grain grinding device, although the fraction distributor, made in the form of a set of solid cones, which are expanded stepwise by their bases to the disk, ensures grain calibration by size into fractions, destruction of grain particles with one blow and removal of small particles from the crushing chamber as they are formed, however, the execution of the working surfaces of the inner cone in the form of sieves reduces the productivity of the device due to possible hanging of grain on the working surfaces. In addition, small particles of the grain mixture getting into the grinding in the central part of the chamber, and large ones - on the periphery, close the holes of the mesh partition, as a result of which the conditions for the removal of small particles from the grinding chamber worsen. Small particles on the surface of the layer are constantly subjected to the impact of the rods and are over-ground. All this leads to an increase in the energy intensity of the process and unevenness of the fractional composition of the crushed particles.

The technical result of the utility model is an improvement of the device for grinding grain, in which, through modernization based on a new interaction of structural elements, their mutual arrangement and interconnection, an increase in the productivity of the device, the quality of grinding and a decrease in the energy intensity of the process are ensured.

The stated technical result is achieved by the fact that in a grain grinding device comprising a housing, a disk located in its cavity, in which wedge-shaped channels are made, expanding from the center to the periphery, a shaft, radially to which working elements in the form of thin rods are fixed, located in several rows, above which a feed hopper is installed, made in the form of two cones - an external and an internal one, turned by their bases to the disk, from which they are separated by a cylindrical mesh partition, which tightly covers the disk, as well as a fraction distributor, made in the form of a set of solid cones, which are stepwise expanded by their bases to the disk, according to the utility model, the inner cone is made in the form of a set of separating cones with a brachistochronic surface, between which slotted openings are located, the number of which corresponds to the number of solid cones of the fraction distributor, and the size depends on the equivalent diameter of the separated particles and is determined by the formula

where L is the width of the slot opening between the separating cones;

d - equivalent diameter of separated particles in a given slot opening.

The essence of the utility model is explained by drawings, where

Fig. 1 - a diagram of the device, side view;

fig. 2 - node I in Fig. 1;

Fig. 3 - top view of the disk;

Fig. 4 - general view of separating cones with a brachistochronic surface.

The device for grinding grain contains a body 1, a disk 2 located in its cavity, radially to which working elements in the form of thin rods 4 are fixed on a shaft 3, located in several rows, above which a feed bin 5 is installed, made in the form of two cones - an external 6 and an internal 7, turned by their bases towards the disk 2, from which they are separated by a cylindrical mesh partition 8.

The inner cone 7 is made in the form of a set of separating cones, with a brachistochronic surface 9, between which there are slotted openings 10, 11, 12, the number of which corresponds to the number of solid cones of the fraction distributor 13, which is installed under the inner cone 7. The width of the slotted opening L depends on the equivalent diameter d of the separated particles of each fraction and is determined by the formula

For example, for separating a grain mixture of a fractional composition with an equivalent diameter of up to 7 mm, for separating a large fraction with an equivalent diameter of more than 6 mm, a slot opening 10 with a width of 20 mm is installed, for separating a medium fraction with an equivalent diameter of 5...6 mm, a slot opening 11 with a width of 13 mm is installed, and for a small fraction, a slot opening 12 is installed with a width of 11 mm.

The fraction distributor 13 is made in the form of a set of solid cones 14, 15 and 16, which expand stepwise with their bases towards the disk 2. Cone 14 serves to receive and distribute the large grain fraction, which is separated through the slot opening 10 of the inner cone 7 (shown by arrow I). Cone 15 is for the medium fraction (arrow II), which is separated through the slot opening 11, and cone 16, respectively, is for the small fraction (arrow III). The separating and distributing cones are made with the possibility of vertical adjustment of the height of each cone separately.

In disk 2, separation channels 17 are made in a wedge-shaped form, expanding from the center to the periphery, and formed by conical sloping corners 18.

Above the feed bin 5, there is a dosing bin 19. At the bottom, the device has an outlet pipe 20.

The grain crushing device operates as follows. Preliminarily cleaned grain without sorting into fractions by size enters through the dosing hopper 19 into the feed hopper 5, where, passing along the surfaces 9 of the brachistochronic property of the internal cone 7, it is distributed into fractions, according to the slot openings 10, 11, 12, for example, into three fractions, as shown in the drawing by arrows I, II, III. Each grain fraction is separately and uniformly distributed by the fraction distributor 13. The large fraction enters the surface of the distribution cone 14, the medium - onto the cone 15, the small - onto the cone 16. Such a feed ensures a uniform supply of grain of each fraction separately to its part of the disk 2, where a single direct impact is realized in the plane perpendicular to the plane of the grain fall by rods 4, located radially on the shaft 3, uniformly along the entire circumference. The crushed grain mixture falls on the disk 2 and moves along the conical sloping corners 18, acquiring the necessary speed under the action of centrifugal forces. When the particles of the mixture move along the conical sloping corners 18, they are separated according to their size through the wedge-shaped channels 17 and are removed from the crushing zone, as shown in the drawing by arrows IV. Such an execution of the wedge-shaped separating channels 17, which expand from the center of the disk 2 to the periphery, and formed by the conical sloping corners 18, eliminates their clogging with particles whose size is equal to the size of the openings or slightly exceeds it. Particles whose size exceeds the maximum size of the separating channels 17 of the disk 2 and particles that are not separated through the channels of the disk are thrown at high speed by centrifugal forces onto the cylindrical mesh partition 8 and are removed through its openings, as shown in the drawing by arrows V. Particles whose size exceeds the size of the openings of the mesh partition 8 are reflected from it (as shown in the drawing by arrows VI), enter the zone of action of the rods 4, are crushed by them additionally and are separated according to their size through the channels 17, or openings of the mesh partition 8 and are removed from the crushing zone, as shown in the drawing by arrows IV, or V.

Next, the crushed products enter the outlet pipe 20 and are discharged from the device.

Thus, the creation of directed flows of grains of uniform size for grinding by direct impact using brachistochronic surfaces with slotted holes allows for the rational organization of the grinding process, the reduction of the circulation load in the grinding chamber and the improvement of the quality of the process.

Claims (4)

A device for grinding grain, comprising a housing, a disk located in its cavity, in which wedge-shaped channels are made, expanding from the center to the periphery, a shaft, radially to which working elements in the form of thin rods are fixed, located in several rows, above which a feed hopper is installed, made in the form of two cones - an external and an internal one, turned by their bases to the disk, from which they are separated by a cylindrical mesh partition that tightly covers the disk, as well as a fraction distributor, made in the form of a set of solid cones, which are stepwise expanded by their bases to the disk, characterized in that the inner cone is made in the form of a set of separating cones with a brachistochronic surface, between which slotted holes are located, the number of which corresponds to the number of solid cones of the fraction distributor, and the size depends on the equivalent diameter of the separated particles and is determined by the formula where L is the width of the slot opening between the separating cones; d - equivalent diameter of separated particles in a given slot opening.