RU2785379C1 - Centrifugal disk grinder - Google Patents

Abstract

FIELD: materials grinding.

SUBSTANCE: invention relates to devices for grinding various materials and can be used in the production of building materials, as well as in other industries. The centrifugal disk grinder contains a cylindrical body 1 with loading 2 and unloading 3 branch pipes, oppositely rotating upper 4 and lower 5 discs. The lower disk 5 has an upper conical surface 7 with an angle α of the inclination of the generatrix to the horizon, exceeding the angle β of the natural repose of the material. The gap between the upper conical surface 7 of the lower disk 5 and the lower conical surface 8 of the upper disk 4 decreases uniformly from the center of disks 4 and 5 to their periphery from 2D_max to (0.1…0.5) D_max, where D_max is the maximum particle size of the crushed material , forming an angle between the lower conical surface 8 of the upper disk 4 and the upper conical surface 7 of the lower disk 5, on which curved ribs 9 and 10 are fixed in the direction of rotation of the corresponding disk. In the upper ends of the curved ribs 10 of the lower disk 5, rectangular grooves 11 are made uniformly and sequentially one after another from the center to the periphery, and on the lower ends of the curved ribs 9 of the upper disk 4, rectangular protrusions 12 are made uniformly and sequentially one after another from the center to the periphery, the height and the radial size of which, as well as the height and radial size of the rectangular grooves 11 and the height of the curvilinear ribs 9 and 10 of the two disks 4 and 5 decrease from the center of the disks 4 and 5 to their periphery in proportion to the decrease in the gap between the conical surfaces of the upper 4 and lower 5 disks. Rectangular protrusions 12 of the curved ribs 9 of the upper disk 4 are located in the corresponding rectangular grooves 11 of the curved ribs 10 of the lower disk 5 to provide a technological clearance. The minimum distance between adjacent curved ribs 10 of the lower disk 5 exceeds D_max.

EFFECT: grinder provides an increase in the efficiency of the grinding process.

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Description

The invention relates to devices for grinding 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 the BSTU named after V.G. Shukhova, 2018, No. 5, pp. 78-81), containing a cylindrical body, inside of which there are two upper and lower discs rotating in opposite directions with a conical working surface.

A known design of a centrifugal impact mill (USSR author's certificate for the invention No. 671839, VO2S 13/14, publ. 05.07.1979, bull. No. 25), containing a stepped housing, each subsequent stage in which, counting in the direction of movement of the material, is made of a larger diameter , a stepped rotor with beaters horizontally located in the housing, a loading and unloading branch pipe.

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

The closest technical solution to the proposed one, adopted as a prototype, is a centrifugal disc grinder (RF Patent for utility model No. 145376, VS 13/20, publ. oppositely 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 disks.

With the essential features of the claimed invention coincides with the following set of features of the prototype: a cylindrical body with loading and unloading nozzles and oppositely rotating upper and lower discs.

However, the known device is characterized by low efficiency of the grinding process. This is due to insignificant loads on the crushed material and the absence of a selective effect on the material depending on its size.

The invention is aimed at improving the efficiency of the grinding process by increasing the load on the crushed material and the selective effect on the material depending on its size.

This is achieved by the fact that the centrifugal disc grinder contains a cylindrical body with loading and unloading nozzles, oppositely rotating upper and lower discs. According to the proposed solution, the lower disk has an upper conical surface with an inclination angle of the generatrix to the horizon exceeding the angle of repose of the material. The gap between the upper conical surface of the lower disc and the lower conical surface of the upper disc decreases uniformly from the center of the discs to their periphery from 2D _max to (0.1...0.5) D _max , where D _max is the maximum particle size of the crushed material, forming the angle between the lower conical surface of the upper disk and the upper conical surface of the lower disk, on which curvilinear ribs are rigidly fixed in the direction of rotation of the corresponding disk. In the upper ends of the curvilinear ribs of the lower disk, rectangular grooves are made evenly and sequentially one after another from the center to the periphery. On the lower ends of the curvilinear ribs of the upper disk, rectangular protrusions are made uniformly and sequentially one after another from the center to the periphery, the height and radial size of which, as well as the height and radial size of the rectangular grooves, and the height of the curvilinear ribs of the two disks decrease from the center of the disks to their periphery proportionally reducing the gap between the conical surfaces of the upper and lower disks. Rectangular protrusions of the curvilinear ribs of the upper disk are located in the corresponding rectangular grooves to provide a technological gap. The minimum distance between adjacent curved ribs of the lower disk exceeds D _max .

The essence of the invention is illustrated by the drawing, where figure 1 shows a longitudinal section of the chopper; figure 2 - section A-A in Fig. 1 (curvilinear ribs with rectangular grooves); in fig. 3 - section B-B in Fig. 1 (curvilinear ribs with rectangular protrusions).

The centrifugal disc grinder contains a cylindrical body 1 with loading 2 and unloading 3 branch pipes, oppositely rotating upper 4 and lower 5 disks. The upper disk 4 rotates from the loading pipe 2, and the lower disk 5 rotates from the lower shaft 6. The lower disk 5 has an upper conical surface 7 with an inclination angle β of the generatrix to the horizon exceeding the angle α of the natural repose of the material. The gap between the upper conical surface 7 of the lower disk 5 and the lower conical surface 8 of the upper disk 4 decreases uniformly from the center of disks 4 and 5 to their periphery from 2D _max to (0.1…0.5) D _max , where D _max is the maximum size particles of the crushed material, forming an angle between the lower conical surface 8 of the upper disk 4 and the upper conical surface 7 of the lower disk 5, on which curved ribs, respectively, 9 and 10, are rigidly fixed, for example by welding, in the direction of rotation of the corresponding disk. The height of the curved ribs 9 and 10 decreases uniformly from the center of the discs 4 and 5 to their periphery in proportion to the decrease in the gap between the lower conical surface 8 of the upper disc 4 and the upper conical surface 7 of the lower disc 5. after the other from the center to the periphery, rectangular grooves 11 are made, the height and radial size of which decrease from the center of the disks 4 and 5 to their periphery in proportion to the decrease in the gap between the conical surfaces 7 and 8 of the two disks 4 and 5. At the lower ends of the curved ribs 9 of the upper disk 4 rectangular protrusions 12 are made evenly and sequentially one after another from the center to the periphery, the height and radial size of which decrease from the center of the disks 4 and 5 to their periphery in proportion to the decrease in the gap between the conical surfaces 7 and 8 of the two disks 4 and 5. Rectangular protrusions 12 curvilinear ribs 9 upper disk 4 are located in the respective rectangular grooves 11 curvilinear ribs 10 of the lower disk 5 with the technological gap. The minimum distance between adjacent curved ribs 10 of the lower disk 5 exceeds D _max . If necessary, it is possible to raise the upper disk 4 due to the spring support 13.

Centrifugal disc grinder works as follows. The crushed material, for example, limestone with a moisture content of up to 2%, enters the loading pipe 2, then into the working volume between the conical surfaces of the lower 5 and upper 4 discs rotating in opposite directions from the lower shaft 6 and the loading pipe 2, respectively. The material particles are directed to the upper conical surface 7 of the lower disk 5, and fall on the working surface of the curved ribs 10 of this disk. Particles of material are captured by curvilinear ribs 10 of the lower disk 5 and move along their working surface. When this occurs, the destruction of the particles between the working surfaces of the curved ribs 9, rigidly fixed on the lower conical surface 8 of the upper disk 4 and curved ribs 10, rigidly fixed on the upper conical surface 7 of the lower disk 5, rotating in opposite directions. Upon reaching the first rectangular groove 11, the largest particles are destroyed in the technological gap between the rectangular groove 11 and the rectangular protrusion 12 of the curved ribs 9 and 10 of the upper 4 and lower 5 disks due to shear, crush and abrasion loads. With further movement of the particles along the working surface of the curvilinear ribs 10 of the lower disk 5, the particles are destroyed in the technological gaps of the subsequent rectangular grooves 11 and rectangular protrusions 12. Since the particles, when moving from the center of the disks 4 and 5 to their periphery, decrease in size, respectively, the dimensions of the rectangular grooves decrease. 11 and rectangular ledges 12. When the required size is reached, the material particles are directed towards the periphery of the lower disk 5. Indestructible pieces of material are unloaded by raising the upper disk 4 when the spring support 13 is compressed. The finished product flies out of the housing 1 through the discharge pipe 3. To increase the intensity of particle movement from the center of the lower disk 5 to its periphery, the upper surface 7 of the lower disk 5 is made conical with the generatrix inclination angle β exceeding the natural repose angle α of the material. Since the particles of the material when moving from the center to the periphery of the disks 4 and 5 decrease in size, accordingly, the height of the curvilinear ribs 9 and 10 of the two disks 4 and 5 decreases from their center to the periphery. To prevent clogging of the gaps between the curved ribs 10, the minimum distance between adjacent curved ribs 10 of the lower disk 5 exceeds D_max.

The design of a centrifugal disc grinder with counter-rotating upper and lower discs with curved ribs, as well as with rectangular protrusions and rectangular grooves, allows for increased loads on the crushed material and a selective effect on the crushed material depending on the size of the particles. All of the above will improve the efficiency of the grinding process, thereby increasing productivity in terms of the finished class of crushed material.

Claims (1)

Centrifugal disk grinder containing a cylindrical body with loading and unloading pipes, oppositely rotating upper and lower disks, characterized in that the lower disk has an upper conical surface with an inclination angle of the generatrix to the horizon exceeding the angle of repose of the material, the gap between the upper conical surface of the lower disk and the lower conical surface of the upper disk decreases uniformly from the center of the disks to their periphery from 2D _max to (0.1 ... 0.5) D _max , where D _max is the maximum particle size of the crushed material, forming an angle between the lower conical surface of the upper disk and the upper the conical surface of the lower disk, on which the curved ribs are rigidly fixed in the direction of rotation of the corresponding disk, in the upper ends of the curved ribs of the lower disk, rectangular grooves are made uniformly and sequentially one after another from the center to the periphery, and on the lower ends of the curved ribs of the upper disk, equal straight and sequentially one after another from the center to the periphery, rectangular protrusions are made, the height and radial size of which, as well as the height and radial size of the rectangular grooves and the height of the curvilinear ribs of the two disks decrease from the center of the disks to their periphery in proportion to the decrease in the gap between the conical surfaces of the upper and lower disks, while the rectangular ledges of the curved ribs of the upper disk are located in the corresponding rectangular grooves with a technological gap, and the minimum distance between adjacent curved ribs of the lower disk exceeds D _max .

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