RU2496581C1 - Mill - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to grinding-dressing equipment for grinding of minerals. Proposed mill comprises frame and crossbar, top rotor with lateral sieving surfaces and top loading openings. Rotor houses post and post jacket, bottom rotor with radial ribs, bearing assemblies and V-belt pulleys, drive motor and intake bin.Mill accommodates extra shaft thrusting by one end against bearing assy and by opposite end coupled by half-coupling with drive motor. Gear ratios of articulation of top and bottom branches of the loop composed by extra shaft, drive and driven pulleys of top branch with appropriate V-belts, drive and driven pulleys of bottom branch with appropriate V-belts are not equal.

EFFECT: power savings owing to circulating power in closed loop.

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Description

The invention relates to crushing, processing and construction equipment for the production of materials used in the construction materials industry, mining, chemical and metallurgical industries, and can find application in the enrichment and processing of mineral raw materials and industrial wastes.

Close in technical essence to the invention is a dynamic self-grinding mill containing a housing in which there is a shaft, a cup-shaped rotor with radial ribs, screening surfaces, a removable and upper rings, a loading pipe, a cover, a funnel, a discharge chute, screw jacks, bearing units and a pulley V-belt transmission (KHETAUROV VN Development and design of vertical-type centrifugal mills, Vladikavkaz, Terek, 1999, p.20, Fig. 1.2).

The disadvantage of the mill of this design are the relatively high specific energy consumption.

Closest to the technical nature of the invention is a dynamic self-grinding mill according to RU 2234373 A1, (20.08.2004), comprising a housing in which a shaft, a cup-shaped rotor with radial ribs, sifting surfaces, a removable and upper rings, a loading nozzle, a cover, a funnel are located , discharge chute, screw jacks, bearing units and V-belt drive pulley; the mill is equipped with a closing kinematic mechanism consisting of gears fixed in the upper and lower parts of the rotor shaft and engaged with gears coaxially located relative to each other, and a loading device using a closed loop circulating power created by a moment loaded within the limits of the elastic torsion deformation of the shaft, equal to the moment at which the material is destroyed.

The disadvantage of this type of dynamic self-grinding mill is the complexity of its design scheme.

The technical result obtained by the implementation of the claimed mill is the simplification of the design, the possibility of using mass-produced by the industry electric motors and reducing due to this operating costs.

The objective of the claimed technical solution is the additional power impact on the pieces of the crushed material, as well as reducing operating costs by simplifying the design.

The specified technical result is achieved in that the mill contains a frame and a cross member, a rotating upper rotor with side screening surfaces and upper loading holes, in which the rack and shirt stand, the lower rotor with radial ribs, bearing assemblies and V-belt pulleys, an electric motor, a receiving hopper in this case, an additional shaft has been introduced, resting at one end into the bearing support, and connected to the electric motor with half-couplings at the other, and the gear ratios of the kinema gears in the upper and lower branches of the contour formed by the additional shaft, the driving and driven pulleys of the upper branch with their corresponding V-belts, the driven and driving pulleys of the lower branch with their corresponding V-belts, are not equal to each other.

Figure 1 schematically shows the claimed mill;

figure 2 is a view of figure 1; figure 3 - rotors on an enlarged scale.

The mill contains a frame 1 on which an electric motor 2 is mounted, at the end of the rotor of which a half-coupling 4 of an electric motor 2 is mounted, connected to a half-coupling 5 of an additional shaft 7, which is mounted at the lower end in the lower bearing 9.

On the additional shaft 7, a driving pulley 6 of the drive of the upper rotor 14 and a driving pulley 8 of the lower rotor 13 are mounted. The rotation is transmitted to the lower rotor 13 and the upper rotor 14 through V-belt drives through the driven pulley 16 of the upper rotor 14 and the driven pulley 11 of the lower rotor 13. Kinematic gears from the electric motor 2 to the lower rotor 13 and the upper rotor 14 can be of any type: V-belt, as in this example (flat, round), as well as gear, chain, using other types of gears (screw, worm, etc. )

The lower rotor 13 is mounted on a strut 19, which has a lower end mounted rigidly on the frame 1, and the upper end is mounted in the upper bearing assembly 18 mounted in the bearing housing 20, and it is rigidly mounted on the cross member 3 connected with the frame 1; the rotor 13 can freely rotate in the bearing assembly 10 mounted on the rack 19.

A protective tube 15 is installed on the rack 19, the purpose of which is to protect the rack 19 from wear by crushed material located in the inner cavity of the lower 13 and upper 14 rotors. The protective tube 15 located in the inner cavity of the upper rotor 14, the upper end is fixed rigidly with bolt or other types of fasteners to the driven pulley 16 of the drive of the upper rotor 14 and rotates with it, and rotates with the lower end in the bearing assembly 24.

To load the cavities of the upper 14 and lower 13 rotors with the starting material, loading funnels 17 are made in the upper part.

To ensure the tightness of the grinding process of the feed material in the lower part of the upper rotor 14, a ring 22 is mounted using bolted connections.

To ensure the discharge of crushed material from the working area in the lower part of the upper rotor 14 is made around the perimeter of the hole (figure 3).

To collect the crushed material, the size of which is smaller than the size of the side holes in the upper rotor 14, a receiving hopper 12 is installed.

The mill has a closing kinematic circuit formed by an additional shaft 7, a driving pulley 8, a driven pulley 11 with their corresponding V-belts, material located in the cavities of the lower 13 and upper 14 rotors, a driven 16 and a leading 6 pulleys with their corresponding V-belts.

The gear ratios of the kinematic gears in the upper and lower branches of the contour formed by the additional shaft 7, the driving pulley 8, the driven pulley 11 with their corresponding V-belts, the driven 16 and the leading 6 pulleys with their corresponding V-belts, are not equal to each other.

The mill operates as follows.

In the upper rotor 14 through the feed funnel 17, made in its upper part, the source material is portioned. During operation, an updated column of pieces of material is constantly formed above the lower rotor 13. When the electric motor 2 is turned on, pieces of crushed material located in the cavity of the upper rotor 14 and above the lower rotor 13 begin to move to its periphery under the action of centrifugal force, while simultaneously pressing against the radial ribs 21 , and, once in the active zone, are crushed due to impacts, chipping and abrasion. Particles of material commensurate with the size of the side holes made in the lower part of the upper rotor 14 are discharged through these holes by centrifugal force and enter the receiving hopper 12. Particles of material larger than the size of the holes in the side surface of the upper 14 move along it in an ascending toroidal line and then, together with the original lumpy material and partially crushed, they are previously lowered into the working zone of the cavity of the lower rotor 13.

Moreover, due to different gear ratios in the lower and upper branches of the mill, a kinematic mismatch of the rotations of the upper 14 and lower 13 rotors is formed. Due to this discrepancy, the angular velocities of the inner 13 and outer 14 rotors lag behind each revolution relative to each other.

This makes it possible to use the circulating power arising in the described closed loop. The circulating power is created in a closed kinematic circuit due to the elastic properties of its elements due to their gradual and increasing “regression”, which leads to the fact that the crushed material is subjected to loads much more than those created by the drive motor 2.

This provides a more intense destruction and crushing of pieces of the crushed material due to the increased contact stress between them when the occurrence of circulating energy. The toroidal movement of the crushed pieces due to their increased kinetic energy due to the entrainment of the pieces of crushed material by the rotating external rotor 13 will contribute to their intensive mixing and, therefore, abrasion and cracking.

When a certain moment is reached, determined by the moment of friction resistance arising between the layers of the crushed lumpy bulk material located above the lower rotor 13 in a stressed state, depending on the angle of internal friction and the specific pressure force, its “continuity” along the slip lines will break and the closed kinematic will be disconnected. contour due to slippage of layers of stressed material relative to each other.

After reaching the state of equilibrium between the layers of the crushed material, caused by the receipt of an additional portion of the material from the outside, and increasing due to this specific pressure on the lower layers of the material, the slipping of the layers of the crushed material relative to each other will stop. The system again closes and returns to its original state, in which there will be no lag in the angular velocities of the upper 14 and lower 13 rotors relative to each other in a closed mill circuit.

After this cycle, the process is repeated many times in the same sequence until the desired degree of grinding of the material, withdrawal and accumulation of it in the receiving hopper 12 through the side holes made in the lower part of the upper rotor 14 is achieved.

Claims (1)

A mill containing a frame and a cross member, a rotating upper rotor with side screening surfaces and upper feed openings, in which the rack and shirt stand, the lower rotor with radial ribs, bearing assemblies and V-belt pulleys, an electric motor, a receiving hopper, characterized in that it is introduced an additional shaft resting on one end in a bearing support, and on the other connected by means of a coupling with an electric motor, the gear ratios of the kinematic gears in the upper and lower The lines of the contour formed by the additional shaft, the leading and driven pulleys of the upper branch with their corresponding V-belts, the driven and leading pulleys of the lower branch with their corresponding V-belts, are not equal to each other.

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