RU2840465C1 - Centrifugal disc grinder - Google Patents

Abstract

FIELD: crushing or grinding of various materials.

SUBSTANCE: invention relates to grinders of various materials and may be used in production of construction materials, as well as in other industries. Centrifugal disc grinder comprises cylindrical housing 1 with loading 2 and unloading 3 nozzles, oppositely rotating upper 4 and lower 5 discs. On lower surface of upper conical disk 4 and on upper surface of lower horizontal disk 5 there rigidly fixed are vertical curvilinear blades 7 and 8 bent in direction of rotation of disks 4 and 5 and having rectangular cross section. Vertical gap between the upper conical disc 4 lower surface and the lower horizontal disc 5 upper surface evenly decreases from their centre to periphery from (1.5...2)D_max to (0.2...0.5)D_max, where D_max is the maximum particle size of the crushed material. Height of vertical curved blades 7 and 8 of upper conical 4 and lower horizontal 5 discs decreases from centre to periphery from (0.5...1.0)D_max proportional to reduction of vertical gap between surfaces of discs 4 and 5 with process clearance between vertical curved blades 7 and 8. On the upper surface of the lower horizontal disc 5 with a radial pitch exceeding D_max, in front of the working surface of each vertical curved blade 8 in the direction of its rotation, vertical pins 9 of a circular cross section are rigidly attached, which height decreases from the centre to the periphery similarly to the vertical curved blades 8 height decreasing, with the gap between them and vertical fingers 9 exceeding the vertical curved blades 8 corresponding height. In the centre of lower horizontal disc 5 vertical cylindrical accumulator 10 with an inner diameter equal to the inner diameter of loading pipe 2 is rigidly fixed, inside of which vertical blades 11 are rigidly fixed, by the outer ends adjacent to the vertical curved blades 8 inside each vertical cutout 12 with width of 2Dmax in the vertical cylindrical accumulator 10, made in the direction of rotation of the lower horizontal disc 5.

EFFECT: increasing the efficiency of the grinding process.

1 cl, 3 dwg

Description

The invention relates to devices for crushing various materials and can be used in the production of building materials, as well as in other industries.

The design of a centrifugal disc grinder is known (Semikopenko I.A., Voronov V.P., Belyaev D.A., Manyakhin A.S. Determination of the power spent on grinding a particle between two conical surfaces // Bulletin of BSTU named after V.G. Shukhov. 2018. No. 5. Pp. 78-81), containing a cylindrical body, inside which there are two upper and lower discs with a working surface rotating in opposite directions.

A design of a centrifugal impact mill is known (USSR Author's Certificate for Invention No. 671839, B02C13/14, published on 07/05/1979, Bulletin No. 25), comprising a stepped housing, each subsequent stage of which, counting along the direction of movement of the material, is made of a larger diameter, a stepped rotor with beaters located horizontally in the housing, a loading and unloading branch pipe.

The technical problem of known designs is the low efficiency of the grinding process and low fineness of grinding.

The closest technical solution to the proposed one, adopted as a prototype, is a centrifugal disc grinder (Patent of the Russian Federation for Utility Model No. 145376, B02 C 13/20, published on 20.09.2014, Bulletin No. 26), containing a cylindrical body with loading and unloading pipes, counter-rotating flat upper and lower discs with impact elements, the impact elements are made in the form of a spiral, which are directed in opposite directions on the upper and lower discs.

The following set of features of the prototype coincide with the essential features of the claimed invention: a cylindrical body with loading and unloading pipes and counter-rotating upper and lower disks.

However, the known device is characterized by low efficiency of the grinding process. This is due to insufficient loads on the material and the lack of selective action on the crushed particles of the material as they move from the center of the disks to the periphery.

The invention is aimed at increasing the efficiency of the grinding process due to increased loads on the material and selective action on the grinding particles of the material as they move from the center of the disks to the periphery.

This is achieved by the fact that the centrifugal disc crusher contains a cylindrical body with loading and unloading pipes, counter-rotating upper conical and lower horizontal discs. According to the proposed solution, vertical curved blades bent in the direction of rotation of the discs and having a rectangular cross-section are rigidly fixed on the lower surface of the upper conical disc and on the upper surface of the lower horizontal disc. The vertical gap between the lower surface of the upper conical disc and the upper surface of the lower horizontal disc uniformly decreases from their center to the periphery from (1.5...2)D _max to (0.2...0.5)D _max , where D _max is the maximum particle size of the material being crushed. The height of the vertical curved blades of the upper conical and lower horizontal discs decreases from the center to the periphery from (0.5...1.0)D _max in proportion to the decrease in the vertical gap between the surfaces of the discs with the technological gap between the vertical curved blades. On the upper surface of the lower horizontal disk with a radial pitch exceeding D _max , in front of the working surface of each vertical curved blade in the direction of its rotation, vertical fingers of a circular cross-section are rigidly attached, the height of which decreases from the center to the periphery similar to the decrease in the height of the vertical curved blades, with a gap between them and the vertical fingers exceeding the corresponding height of the vertical curved blade. In the center of the lower horizontal disk, a vertical cylindrical accumulator is rigidly attached with an internal diameter equal to the internal diameter of the loading branch pipe, inside which vertical blades are rigidly fixed, adjacent with their outer ends to the vertical curved blades inside each vertical cutout of width 2D _max in the vertical cylindrical accumulator, made in the direction of rotation of the lower horizontal disk.

The essence of the invention is explained by the figures, where Fig. 1 shows a longitudinal section of a centrifugal disc crusher; Fig. 2 is a section A-A in Fig. 1 (vertical curved blades of the lower horizontal disc); Fig. 3 is a section B-B in Fig. 1 (vertical curved blades of the upper conical disc).

The centrifugal disc crusher comprises a cylindrical body 1 with a loading 2 and unloading 3 branch pipes, counter-rotating upper conical 4 and lower horizontal 5 discs. The upper conical disc 4 rotates from the loading branch pipe 2, and the lower horizontal disc 5 rotates from the lower shaft 6. On the lower surface of the upper conical disc 4 and on the upper surface of the lower horizontal disc 5, vertical curved blades 7 and 8, respectively, are rigidly fixed, for example by welding, bent in the direction of rotation of the discs 4 and 5 and having a rectangular cross-section. The vertical gap between the lower surface of the upper conical disc 4 and the upper surface of the lower horizontal disc 5 uniformly decreases from their center to the periphery from (1.5...2)D _max to (0.2...0.5)D _max , where D _max is the maximum particle size of the material being crushed. The height of the vertical curved blades 7 and 8 of the upper conical 4 and lower 5 horizontal disks decreases from the center to the periphery from (0.5...1.0)D _max in proportion to the decrease in the vertical gap between the lower surface of the upper conical disk 4 and the upper surface of the lower horizontal disk 5 with a technological gap between the vertical curved blades 7 and 8. On the upper surface of the lower horizontal disk 5 with a radial pitch exceeding D _max , in front of the working surface of each vertical curved blade 8 in the direction of its rotation, vertical fingers 9 of a circular cross-section are rigidly attached, for example by welding, the height of which decreases from the center to the periphery similarly to the decrease in the height of the vertical curved blades 8, with a gap between them and the vertical fingers 9 exceeding the corresponding height of the vertical curved blade 8. In the center of the lower horizontal disk 5, a vertical cylindrical accumulator 10 with an internal diameter equal to the internal diameter of the loading pipe 2. Inside the vertical cylindrical accumulator 10, vertical blades 11 are rigidly fixed, for example by welding, adjoining the outer ends of the vertical curved blades 8 inside each vertical cutout 12 of width 2D _max , made in the vertical cylindrical accumulator 10. Each vertical cutout 12 is made in the direction of rotation of the lower horizontal disk 5. If necessary, it is possible to raise the upper conical disk 4 due to the spring support 13.

The centrifugal disc crusher works as follows. The crushed material, for example limestone with a moisture content of up to 1%, enters the loading branch pipe 2, then into the working volume between the upper surface of the lower horizontal disk 5 and the lower surface of the upper conical disk 4, rotating in opposite directions, respectively, from the lower shaft 6 and the loading branch pipe 2. The material particles are directed to the upper surface of the lower horizontal disk 5, then, under the action of centrifugal force, they move along the working surfaces of the vertical blades 11 through the vertical cutouts 12 of the vertical cylindrical accumulator 10 to the adjacent vertical curved blades 8, located inside each vertical cutout 12. During the radial movement of the particles of the crushed material along the working surfaces of the vertical curved blades 8, the particles are continuously affected by the vertical curved blades 7 and 8 rotating in opposite directions, belonging to the upper conical 4 and lower horizontal 5 disks. In this case, continuous destruction of particles of the corresponding sizes is carried out in the technological gap between the ends of the vertical curved blades 7 and 8. Since the vertical gap between the lower surface of the upper conical disk 4 and the upper surface of the lower horizontal disk 5 is uniformly reduced from the center to the periphery from (1.5...2)D_maxup to (0.2...0.5)D_max, the effect on the particles is selective depending on their size. Thus, when moving from the center of disks 4 and 5 in the direction of their periphery, the material is continuously crushed due to impact, crushing and abrasion. In this case, continuous classification of particles by size is carried out by means of vertical fingers 9 of a circular cross-section..Particles that did not pass through the gap between vertical curved blades 8 and vertical fingers 9, are crushed by vertical curved blades 7 and 8 until they continue radial movement in each zone of action of vertical fingers 9. Since the particles decrease in size during this movement from the center to the periphery, the gap between them decreases accordingly. vertical curved blades 8 and vertical fingers 9. The combination of particle crushing and classification is carried out in the area of action of each vertical finger 9. Upon reaching the required size, the material particles move towards the periphery of the lower horizontal disk 5. Uncrushable pieces of material are unloaded by raising the upper conical disk 4 when the spring support 13 is compressed. The finished product is carried out by the air flow from the housing 1 through the unloading branch pipe 3..To prevent jamming of the material between adjacent vertical fingers 9, the radial pitch between them exceeds D_max, and the width of the vertical cutouts 12 is 2 D_max. In order to increase the residence time of particles in the zone of active impact on them from the vertical curved blades 7 and 8, the latter are made with a curved working surface.

The proposed design of a centrifugal disc crusher allows for increased loads on the material and selective impact on the crushed particles of the material as they move from the center of the discs to the periphery. All of the above will increase the efficiency of the grinding process, thereby increasing the productivity of the finished class of crushed material.

Claims (1)

A centrifugal disc crusher comprising a cylindrical body with loading and unloading pipes, counter-rotating upper conical and lower horizontal discs, characterized in that vertical curved blades curved in the direction of rotation of the discs and having a rectangular cross-section are rigidly fixed to the lower surface of the upper conical disc and to the upper surface of the lower horizontal disc, the vertical gap between the lower surface of the upper conical disc and the upper surface of the lower horizontal disc uniformly decreases from their center to the periphery from (1.5...2)D _max to (0.2...0.5)D _max , where D _max is the maximum particle size of the material being crushed, the height of the vertical curved blades of the upper conical and lower horizontal discs decreases from the center to the periphery from (0.5...1.0)D _max in proportion to the decrease in the vertical gap between the surfaces of the discs with a technological gap between the vertical curved blades, on the upper surface of the lower horizontal disc with a radial pitch exceeding D _max , in front of the working surface of each vertical curved blade in the direction of its rotation, vertical fingers of a circular cross-section are rigidly attached, the height of which decreases from the center to the periphery similar to the decrease in the height of the vertical curved blades, with a gap between them and the vertical fingers exceeding the corresponding height of the vertical curved blade, in the center of the lower horizontal disk, a vertical cylindrical accumulator with an internal diameter equal to the internal diameter of the loading branch pipe is rigidly attached, inside which vertical blades are rigidly fixed, adjacent with their outer ends to the vertical curved blades inside each vertical cutout of width 2D _max in the vertical cylindrical accumulator, made in the direction of rotation of the lower horizontal disk.